Table of SynGAP1 Isoform α2 (UniProt Q96PV0-1) Missense Variants.

c.dna	Variant	SGM Consensus	Domain	ClinVar			gnomAD			ESM1b		AlphaMissense			REVEL		FoldX			Rosetta		Foldetta		PremPS		PROVEAN		PolyPhen-2 HumDiv		PolyPhen-2 HumVar		FATHMM		SIFT				PAM		Physical		SASA		Normalized B-factor backbone		Normalized B-factor sidechain		SynGAP Structural Annotation									DOI
				Clinical Status	Review	Subm.	ID	Allele count	Allele freq.	LLR score	Prediction	Pathogenicity	Class	Optimized	Score	Prediction	Average ΔΔG	Prediction	StdDev	ΔΔG	Prediction	ΔΔG	Prediction	ΔΔG	Prediction	Score	Prediction	pph2_prob	Prediction	pph2_prob	Prediction	Nervous System Score	Prediction	Prediction	Status	Conservation	Sequences	PAM250	PAM120	Hydropathy Δ	MW Δ	Average	Δ	Δ	StdDev	Δ	StdDev	Secondary	Tertiary bonds	Inside out	GAP-Ras interface	At membrane	No effect	MD Alert	Verdict	Description
c.2101C>T	P701S (3D Viewer)	Likely Benign	GAP	Uncertain		1	6-33441360-C-T	3	1.86e-6	-4.375	Likely Benign	0.221	Likely Benign	Likely Benign	0.132	Likely Benign	1.33	Ambiguous	0.0	0.12	Likely Benign	0.73	Ambiguous	-0.36	Likely Benign	0.78	Neutral	0.044	Benign	0.025	Benign	3.48	Benign	1.00	Tolerated	3.47	10	-1	1	0.8	-10.04																			10.1016/j.ajhg.2020.11.011
c.1888A>G	I630V (3D Viewer)		GAP	Benign/Likely benign		4	6-33440940-A-G	59	3.66e-5	-7.264	In-Between	0.145	Likely Benign	Likely Benign	0.143	Likely Benign	1.33	Ambiguous	0.0	0.94	Ambiguous	1.14	Ambiguous	0.64	Ambiguous	-0.38	Neutral	0.018	Benign	0.011	Benign	-1.37	Pathogenic	0.35	Tolerated	3.37	34	4	3	-0.3	-14.03	235.0	26.2	-0.1	0.0	-0.3	0.1						X		Potentially Benign	The sec-butyl side chain of Ile630, located in an α helix (res. Glu617-Asn635), packs with hydrophobic residues (e.g., Phe594, Leu633, Ile626, Ile602) in the hydrophobic inter-helix space between two α helices (res. Glu617-Asn635 and res. Glu582-Met603).In the variant simulations, the iso-propyl side chain of Val630, which shares a similar size and physicochemical properties with Ile630 in the WT, maintains similar interactions in the inter-helix space. Although no negative structural effects are observed during the simulations, the implications of the residue swap on the complex formation with the GTPase, due to its location, cannot be investigated using solvent-only simulations.
c.953C>T	P318L (3D Viewer)	Likely Pathogenic	C2	Uncertain		3	6-33437858-C-T	3	1.86e-6	-10.090	Likely Pathogenic	0.958	Likely Pathogenic	Likely Pathogenic	0.624	Likely Pathogenic	1.33	Ambiguous	0.1	0.26	Likely Benign	0.80	Ambiguous	0.43	Likely Benign	-8.96	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	1.82	Pathogenic	0.03	Affected	3.38	23	-3	-3	5.4	16.04	228.6	-68.9	-0.7	0.7	-0.4	0.1						X		Potentially Benign	The cyclic five-membered pyrrolidine ring of Pro318, located in a β hairpin loop linking two anti-parallel β sheet strands (res. Asp330-Ala322, res. Thr305-Asn315), packs against the hydrophobic side chain of Ile205 at the end of the anti-parallel β sheet in the PH domain. In the variant simulations, the iso-butyl side chain of Leu318 is unable to do the same, potentially weakening the PH and C2 domain association. Importantly, the residue swap could also affect loop formation during folding, as proline can make tighter turns than leucine. Because the residue swap could affect the C2 domain stability, it could also negatively impact the SynGAP-membrane association.
c.892C>T	P298S (3D Viewer)	Likely Benign	C2	Benign		1	6-33437797-C-T	5	3.10e-6	-6.342	Likely Benign	0.144	Likely Benign	Likely Benign	0.189	Likely Benign	1.38	Ambiguous	0.2	1.41	Ambiguous	1.40	Ambiguous	0.58	Ambiguous	-1.20	Neutral	0.991	Probably Damaging	0.898	Possibly Damaging	2.03	Pathogenic	0.85	Tolerated	3.39	20	-1	1	0.8	-10.04
c.877C>T	R293C (3D Viewer)	Likely Pathogenic	C2	Uncertain		1	6-33437782-C-T	3	1.86e-6	-12.844	Likely Pathogenic	0.985	Likely Pathogenic	Likely Pathogenic	0.579	Likely Pathogenic	1.38	Ambiguous	0.1	0.62	Ambiguous	1.00	Ambiguous	0.02	Likely Benign	-7.35	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	1.46	Pathogenic	0.00	Affected	3.38	23	-4	-3	7.0	-53.05	226.0	96.5	0.0	0.0	0.1	0.1		X		X			X	Potentially Pathogenic	The guanidinium group of the Arg293 side chain, located in an anti-parallel β sheet strand (res. Met289-Pro298), packs against the phenol ring of the Tyr281 side chain or forms a salt bridge with the carboxylate group of Glu283 on the outer side of the C2 domain. The positively charged guanidinium side chain of arginine is on the outside surface of the hydrophobic C2 domain, resulting in a twist in the β strand. Although this twist is maintained in the variant simulations, replacing the positively charged residue with a more hydrophobic one, such as cysteine, could remove the twist during protein folding.Because Arg293 is positioned at the C2 and PH domain interface, the residue swap could significantly impact the tertiary structure assembly. Notably, Arg293 is located at the SynGAP-Ras interface, and its role in complex formation cannot be fully understood through solvent-only simulations.
c.1485A>C	E495D (3D Viewer)	Likely Pathogenic	GAP	Conflicting		2				-3.574	Likely Benign	0.958	Likely Pathogenic	Likely Pathogenic	0.566	Likely Pathogenic	1.39	Ambiguous	0.1	1.03	Ambiguous	1.21	Ambiguous	0.98	Ambiguous	-2.52	Deleterious	0.998	Probably Damaging	0.989	Probably Damaging	-1.41	Pathogenic	0.17	Tolerated	3.37	35	3	2	0.0	-14.03	220.6	38.8	0.0	0.0	0.1	0.1		X		X				Uncertain	Glu495 is located in the α-helix (res. Leu489-Glu519), and its carboxylate group forms salt bridges with the neighboring Lys492 and with Arg596 on an opposing α-helix (res. Glu582-Met603) in the WT simulations. In the variant simulations, the acidic carboxylate side chain of Asp495 can also form salt bridges with both Lys492 and Arg596. However, the shorter side chain of aspartate tends to favor forming a salt bridge with the nearby Arg499 on the same α-helix instead. Asp495 might not maintain the salt bridge with Arg596 on the opposing α-helix as efficiently as Glu495 in the WT, potentially weakening the tertiary structure. Regardless, the potential negative effect is likely to be minor, with no deleterious effects observed on the protein structure during the simulations. However, due to its location at the GAP-Ras interface, the effect of the residue swap on SynGAP-Ras complex formation or GTPase activation cannot be fully addressed using the SynGAP solvent-only simulations.
c.1723C>T	R575C (3D Viewer)	Likely Pathogenic	GAP	Conflicting		3	6-33440775-C-T	23	1.43e-5	-11.179	Likely Pathogenic	0.630	Likely Pathogenic	Likely Benign	0.715	Likely Pathogenic	1.39	Ambiguous	0.2	0.50	Ambiguous	0.95	Ambiguous	0.73	Ambiguous	-5.43	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.30	Pathogenic	0.02	Affected	3.37	35	-4	-3	7.0	-53.05	227.7	99.2	0.0	0.0	0.0	0.1		X						Potentially Pathogenic	The guanidinium group of Arg575, located in an α-helix (res. Arg563-Glu578), forms salt bridges with the carboxylate groups of Asp463 and Asp467, and it also hydrogen bonds with the hydroxyl group of Ser466 on an opposing α-helix (res. Ala461-Phe476) in the WT simulations. In the variant simulations, the thiol group of the Cys575 side chain, which is neither positively charged nor particularly hydrophilic, packs against the hydrophobic Met470 on an opposing α-helix (res. Ala461-Arg475). Additionally, although the thiol group is not an effective hydrogen bonder, the Cys575 side chain rotates to hydrogen bond with the backbone carbonyl group of Ser571 in the same α-helix, which could theoretically lower the helix integrity. Overall, the residue swap has the potential to substantially affect the tertiary structure assembly during the protein folding process.
c.662A>G	E221G (3D Viewer)	Likely Pathogenic	PH	Uncertain		1				-12.221	Likely Pathogenic	0.992	Likely Pathogenic	Likely Pathogenic	0.863	Likely Pathogenic	1.40	Ambiguous	0.1	1.74	Ambiguous	1.57	Ambiguous	0.71	Ambiguous	-5.56	Deleterious	0.596	Possibly Damaging	0.201	Benign	5.79	Benign	0.00	Affected			0	-2	3.1	-72.06
c.1256A>G	E419G (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-10.589	Likely Pathogenic	0.956	Likely Pathogenic	Likely Pathogenic	0.469	Likely Benign	1.41	Ambiguous	0.0	1.94	Ambiguous	1.68	Ambiguous	0.83	Ambiguous	-6.42	Deleterious	1.000	Probably Damaging	0.997	Probably Damaging	3.31	Benign	0.02	Affected	3.37	29	0	-2	3.1	-72.06	165.3	110.8	0.0	0.0	-0.1	0.0		X						Potentially Pathogenic	The carboxylate group of Glu419, located on an α helix (res. Met414-Glu436), forms a salt bridge with the side chain of either Arg716 or Lys418 from an opposing helix (res. Pro713-Arg726). The backbone amide group of Glu419 does not form H-bonds, resulting in a slight bend in the α helix. Thus, although glycine is known as an “α helix breaker,” the residue swap does not disrupt the continuity or integrity of the α helix. However, because Gly419 cannot form a salt bridge with the guanidinium group of the Arg716 side chain, the C2-GAP domain tertiary structure could be compromised during folding.
c.1423C>T	R475W (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1	6-33438455-C-T	1	6.20e-7	-13.235	Likely Pathogenic	0.962	Likely Pathogenic	Likely Pathogenic	0.725	Likely Pathogenic	1.44	Ambiguous	0.4	-0.92	Ambiguous	0.26	Likely Benign	0.56	Ambiguous	-7.56	Deleterious	1.000	Probably Damaging	0.995	Probably Damaging	-1.45	Pathogenic	0.00	Affected	3.39	28	2	-3	3.6	30.03	266.9	39.6	0.0	0.0	0.0	0.1	X	X		X				Potentially Pathogenic	In the WT simulations, the guanidinium group of Arg475, located near the end of an α-helix (res. Ala461-Phe476), stacks with the phenyl ring of Phe476 and forms a salt bridge with Glu472. Additionally, Arg475 occasionally forms another salt bridge with the carboxylate group of Glu486 on the α-α loop connecting the two α-helices (res. Ala461-Phe476 and Leu489-Glu519) at the GAP-Ras interface. Therefore, Arg475 potentially plays a key role in positioning the loop by interacting with Glu486, which is necessary for the positioning of the “arginine finger” (Arg485) and, ultimately, for RasGTPase activation.In the variant simulations, Trp475 moves and stacks with Arg479 on the proceeding α-α loop, disrupting the terminal end of the α-helix. Lastly, the potential effect of the residue swap on the SynGAP-Ras complex formation or GTPase activation cannot be fully addressed using the SynGAP solvent-only simulations.
c.2050G>A	D684N (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-13.155	Likely Pathogenic	0.985	Likely Pathogenic	Likely Pathogenic	0.382	Likely Benign	1.47	Ambiguous	0.8	1.76	Ambiguous	1.62	Ambiguous	0.37	Likely Benign	-4.99	Deleterious	0.999	Probably Damaging	0.746	Possibly Damaging	3.39	Benign	0.01	Affected			2	1	0.0	-0.98
c.1193C>T	P398L (3D Viewer)		C2	Uncertain		1	6-33438098-C-T	8	4.96e-6	-7.518	In-Between	0.547	Ambiguous	Likely Benign	0.599	Likely Pathogenic	1.48	Ambiguous	0.2	-0.54	Ambiguous	0.47	Likely Benign	0.62	Ambiguous	-7.10	Deleterious	0.961	Probably Damaging	0.256	Benign	5.72	Benign	0.01	Affected	3.40	16	-3	-3	5.4	16.04	245.8	-68.6	-0.1	0.0	-0.3	0.2							X	Potentially Pathogenic	Pro398 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364 and res. Ala399-Ile411). The Ω loop is assumed to directly interact with the membrane, and it is observed to move arbitrarily throughout the WT solvent simulations. Although the residue swap does not influence the nearby secondary structure elements, proline is often found at the ends of β sheets due to its disfavored status during folding.Additionally, the Ω loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone. Ω loops are known to play significant roles in protein functions that require flexibility, and thus hydrophobic residues like leucine are rarely tolerated. Although no negative structural effects are visualized in the variant’s simulations, Leu398 may exert drastic effects on the SynGAP-membrane complex dynamics and stability. Since the effects on the Gly-rich Ω loop dynamics can only be well studied through the SynGAP-membrane complex, no definite conclusions can be drawn.
c.970C>T	R324W (3D Viewer)	Likely Pathogenic	C2	Uncertain		1	6-33437875-C-T	2	1.24e-6	-12.906	Likely Pathogenic	0.694	Likely Pathogenic	Likely Benign	0.481	Likely Benign	1.49	Ambiguous	0.3	0.56	Ambiguous	1.03	Ambiguous	0.66	Ambiguous	-3.12	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	1.82	Pathogenic	0.16	Tolerated	3.39	22	2	-3	3.6	30.03	256.6	39.1	0.0	0.1	0.3	0.2		X						Potentially Pathogenic	The guanidinium group of Arg324, located at the end of an anti-parallel β sheet strand (res. Ala322-Asp330), faces outward and frequently forms a salt bridge with the carboxylate group of the Asp288 side chain, which is part of a β strand end (res. Met289-Pro298). In the variant simulations, the indole ring of the Trp324 side chain cannot maintain a similar interaction with the negatively charged carboxylate side chain of Asp288, potentially compromising the folding of the anti-parallel β sheet assembly. However, the residue swap does not appear to negatively impact the protein structure or its integrity based on the simulations.
c.745G>A	A249T (3D Viewer)	Likely Benign	PH	Uncertain		1				-3.564	Likely Benign	0.805	Likely Pathogenic	Ambiguous	0.487	Likely Benign	1.50	Ambiguous	0.6	1.39	Ambiguous	1.45	Ambiguous	0.30	Likely Benign	-0.96	Neutral	0.990	Probably Damaging	0.815	Possibly Damaging	5.65	Benign	0.40	Tolerated	3.39	15	1	0	-2.5	30.03	214.5	-43.3	0.0	0.0	0.5	0.2						X		Potentially Benign	The methyl group of Ala249, located on the surface of an α helix (res. Ala236-Val250) facing an anti-parallel β sheet strand (res. Ile205-Val209), packs against nearby hydrophobic residues such as Leu200, Leu246, and Val250. In the variant simulations, the hydroxyl group of Thr249, which is not suitable for hydrophobic packing, forms a stable hydrogen bond with the backbone carbonyl of Asn245 in the same helix. Although this interaction could theoretically weaken the structural integrity of the α helix, this destabilizing effect is not observed in the variant simulations.
c.1787G>T	R596L (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-13.197	Likely Pathogenic	0.992	Likely Pathogenic	Likely Pathogenic	0.756	Likely Pathogenic	1.51	Ambiguous	0.3	-0.58	Ambiguous	0.47	Likely Benign	-0.02	Likely Benign	-6.97	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.45	Pathogenic	0.00	Affected	3.37	35	-3	-2	8.3	-43.03	234.2	63.4	-0.1	0.0	-0.5	0.6		X		X				Potentially Pathogenic	The guanidinium group of Arg596, located in an α helix (res. Glu582-Met603), forms a salt bridge with the carboxylate group of Glu495 from another α helix (res. Leu489-Glu519). In the WT simulations, the side chain of Arg596 hydrogen bonds with the backbone carbonyl groups of Asn487, Glu486, Arg485, and Phe484. Additionally, Arg596 can hydrogen bond with the carboxamide group of the Asn487 side chain on an opposing loop that links two α helices (res. Ala461-Arg475, res. Leu489-Glu519).However, in the variant simulations, the branched hydrocarbon side chain of Leu596 cannot form any of the hydrogen bonds or salt bridges maintained by the considerably bulkier and positively charged Arg596 side chain. Instead, Leu596 packs hydrophobically with the phenyl ring of Phe484 in the linker loop or residues from the opposing helix (e.g., Ile494, Thr491).Thus, the residue swap could affect the tertiary structure assembly more profoundly than observed in the simulations. Notably, Arg596 plays a key role in positioning the aforementioned loop, which is crucial for the placement of the “arginine finger” or the Arg485 side chain during RasGTPase activation.	10.1016/j.ajhg.2020.11.011
c.1474A>G	K492E (3D Viewer)	Likely Pathogenic	GAP	Conflicting		2				-16.175	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.510	Likely Pathogenic	1.53	Ambiguous	0.1	1.90	Ambiguous	1.72	Ambiguous	1.42	Destabilizing	-3.98	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	2.99	Benign	0.01	Affected	3.37	35	1	0	0.4	0.94
c.844T>A	C282S (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-11.846	Likely Pathogenic	0.958	Likely Pathogenic	Likely Pathogenic	0.460	Likely Benign	1.55	Ambiguous	0.1	1.23	Ambiguous	1.39	Ambiguous	1.62	Destabilizing	-9.19	Deleterious	0.997	Probably Damaging	0.994	Probably Damaging	1.64	Pathogenic	0.03	Affected	3.39	18	0	-1	-3.3	-16.06	233.2	14.8	-0.1	0.0	-0.2	0.3						X		Potentially Benign	The thiol-containing side chain of Cys282, located at the beginning of an anti-parallel β sheet strand (res. Arg279-Leu286), packs against multiple hydrophobic residues (e.g., Ile268, Leu284, Trp308, Leu327). In the variant simulations, the hydroxyl-containing side chain of Ser282 is more hydrophilic and, hence, not as favorable as Cys282 for this hydrophobic niche. Due to this polarity difference, the residue swap could potentially weaken the hydrophobic packing of the C2 domain during the folding process.Moreover, because the C2 domain interacts with the membrane, there could also be a negative effect on the stability of the SynGAP-membrane association. However, no large-scale structural changes were observed during the variant simulations. The hydroxyl group of Ser282 forms a hydrogen bond with the backbone carbonyl group of His326 in another β strand (res. Ala322-Arg329), which competes directly with the backbone amide group of Glu283 within the secondary structure element.
c.1997A>G	E666G (3D Viewer)	Likely Pathogenic	GAP	Likely Benign		1	6-33441256-A-G	10	6.20e-6	-12.261	Likely Pathogenic	0.911	Likely Pathogenic	Ambiguous	0.522	Likely Pathogenic	1.57	Ambiguous	0.1	1.46	Ambiguous	1.52	Ambiguous	0.93	Ambiguous	-6.25	Deleterious	1.000	Probably Damaging	0.970	Probably Damaging	3.37	Benign	0.02	Affected	3.38	28	0	-2	3.1	-72.06	173.9	98.5	0.0	0.0	-0.7	0.0		X						Potentially Pathogenic	In the WT simulations, the carboxylate group of Glu666, located on the α-helix (res. Ser641-Glu666), is involved in a highly coordinated hydrogen-bonding network between residues from two α-helices (res. Ser641-Glu666 and res. Arg563-Glu578) and from the α-α loop connecting the two α-helices (res. Ser641-Glu666 and res. Leu685-Val699), such as Lys566, Thr672, and Asn669. In the variant simulations, the carbonyl group of Gly666 occasionally forms hydrogen bonds with Lys566 and Asn669. However, Gly666 lacks a side chain and thus cannot maintain as well-coordinated a hydrogen-bond network as Glu666 in the WT, which may affect the tertiary structure assembly.
c.773G>A	R258H (3D Viewer)		C2	Benign/Likely benign		3	6-33437678-G-A	10	6.20e-6	-10.533	Likely Pathogenic	0.525	Ambiguous	Likely Benign	0.830	Likely Pathogenic	1.60	Ambiguous	0.6	1.00	Ambiguous	1.30	Ambiguous	1.47	Destabilizing	-4.06	Deleterious	1.000	Probably Damaging	0.991	Probably Damaging	5.77	Benign	0.01	Affected	3.39	15	2	0	1.3	-19.05	212.5	81.8	0.1	0.0	-0.5	0.2		X						Potentially Pathogenic	The guanidinium group of Arg258, located at the end of an α-β loop connecting the PH domain to the C2 domain (res. Lys251-Arg258), forms hydrogen bonds with the carboxamide groups of Asn727 and Asn729 side chains, as well as with the backbone carbonyl groups of Ala724, Leu725, and Asn727 in the WT simulations. Although the imidazole group of His258 can act as a hydrogen bond donor/acceptor, the swapped residue is unable to maintain an equally well-coordinated hydrogen bond network for linking the C2 and GAP domains in the variant simulations.
c.1771G>A	A591T (3D Viewer)	Likely Pathogenic	GAP	Conflicting		3	6-33440823-G-A	18	1.12e-5	-9.572	Likely Pathogenic	0.704	Likely Pathogenic	Likely Benign	0.270	Likely Benign	1.61	Ambiguous	0.2	1.00	Ambiguous	1.31	Ambiguous	1.19	Destabilizing	-3.40	Deleterious	0.955	Possibly Damaging	0.209	Benign	3.48	Benign	0.01	Affected	3.37	35	1	0	-2.5	30.03	202.9	-43.4	0.2	0.0	0.7	0.1						X		Potentially Benign	The methyl group of the Ala591 side chain, located in the middle of an α helix (res. Glu582-Met603), packs against hydrophobic residues (e.g., Ile483, Phe484) of an opposing partially helical loop (res. Phe476-Asn487).In the variant simulations, the hydroxyl group of Thr591 can form hydrogen bonds with the backbone carbonyl of Ile843 in the opposing loop or the backbone carbonyl group of Arg587. These interactions could either reinforce the tertiary assembly or weaken the α helix unity. Additionally, the Thr591 side chain can hydrogen bond with the guanidinium group of the Arg587 side chain, potentially strengthening the α helix unity.Overall, the residue swap does not seem to cause any major negative effects on the protein structure.
c.1802C>T	A601V (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-10.447	Likely Pathogenic	0.853	Likely Pathogenic	Ambiguous	0.535	Likely Pathogenic	1.64	Ambiguous	0.1	0.35	Likely Benign	1.00	Ambiguous	0.81	Ambiguous	-3.98	Deleterious	1.000	Probably Damaging	0.989	Probably Damaging	2.74	Benign	0.03	Affected	3.37	35	0	0	2.4	28.05	228.5	-45.5	0.0	0.0	0.4	0.5						X		Potentially Benign	The methyl side chain of Ala601, located on an α helix (res. Glu582-Met603), packs hydrophobically against other hydrophobic residues in the inter-helix space (e.g., Phe597, Leu598, Leu506, Phe608).In the variant simulations, Val601, which has similar size and physicochemical properties to alanine, resides in the inter-helix hydrophobic space in a similar manner to Ala601 in the WT, causing no apparent negative effect on the protein structure. However, the effect of the residue swap on the SynGAP-Ras complex formation or GTPase activation cannot be fully addressed using the SynGAP solvent-only simulations.
c.1465C>T	L489F (3D Viewer)	Likely Pathogenic	GAP	Uncertain		2	6-33438497-C-T	1	6.20e-7	-12.066	Likely Pathogenic	0.965	Likely Pathogenic	Likely Pathogenic	0.724	Likely Pathogenic	1.72	Ambiguous	0.5	1.14	Ambiguous	1.43	Ambiguous	0.56	Ambiguous	-3.76	Deleterious	1.000	Probably Damaging	0.997	Probably Damaging	-1.51	Pathogenic	0.01	Affected	3.37	35	2	0	-1.0	34.02	246.4	-17.8	0.0	0.0	0.6	0.1						X		Potentially Benign	The iso-butyl side chain of Leu489, located in the α-helix (res. Leu489-Glu519) within an inter-helix space of four helices (res. Ala461-Phe476, res. Val441-Ser457, and res. Met414-Glu436), packs with hydrophobic residues (e.g., Cys432, Ala448, Lys444, Ala493, Val447, Met468) in the inter-helix space. In the variant simulations, the phenyl ring of the Phe489 side chain can also pack favorably in the hydrophobic region. However, due to the size difference, the aromatic side chain of Phe489 tends to reposition to escape the tight region to accommodate the larger side chain, stacking with Lys444. Although no apparent negative changes are observed during the variant simulation, the size difference between the swapped residues could affect the protein folding process.
c.1260T>G	F420L (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-8.432	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.146	Likely Benign	1.76	Ambiguous	0.0	1.41	Ambiguous	1.59	Ambiguous	1.04	Destabilizing	-5.39	Deleterious	0.009	Benign	0.005	Benign	4.22	Benign	0.39	Tolerated	3.37	29	2	0	1.0	-34.02	231.1	13.2	0.0	0.0	-0.1	0.0						X		Potentially Benign	In the WT, the phenyl ring of the Phe420 side chain, located on an α helix (res. Met414-Glu436), packs against hydrophobic residues in the interhelix area of the GAP domain (e.g., Leu689, Leu714, Leu717, Leu718). In the variant simulations, the iso-butyl side chain of Leu420 also packs into the hydrophobic inter-helix niche, but due to its smaller size, the resulting steric interactions are not as favorable as with phenylalanine. In short, the residue swap does not cause severe effects on the protein structure based on the variant simulations.
c.1873C>G	L625V	Likely Pathogenic	GAP	Uncertain		1				-11.319	Likely Pathogenic	0.833	Likely Pathogenic	Ambiguous	0.480	Likely Benign	1.80	Ambiguous	0.7	1.69	Ambiguous	1.75	Ambiguous	1.42	Destabilizing	-2.96	Deleterious	0.998	Probably Damaging	0.992	Probably Damaging	3.07	Benign	0.01	Affected			2	1	0.4	-14.03
c.1240A>G	M414V		GAP	Uncertain		1				-8.003	Likely Pathogenic	0.541	Ambiguous	Likely Benign	0.261	Likely Benign	1.81	Ambiguous	0.4	1.73	Ambiguous	1.77	Ambiguous	0.95	Ambiguous	-2.95	Deleterious	0.999	Probably Damaging	0.987	Probably Damaging	3.43	Benign	0.24	Tolerated			2	1	2.3	-32.06
c.1487A>G	E496G (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-13.529	Likely Pathogenic	0.850	Likely Pathogenic	Ambiguous	0.825	Likely Pathogenic	1.83	Ambiguous	0.1	1.76	Ambiguous	1.80	Ambiguous	0.92	Ambiguous	-6.16	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	-1.45	Pathogenic	0.02	Affected	3.37	35	0	-2	3.1	-72.06	173.9	103.1	0.0	0.0	-0.7	0.0		X		X				Potentially Pathogenic	Glu496 is located in the α-helix (res. Leu489-Glu519), and its carboxylate group forms salt bridges with the neighbouring residues Lys492 and Arg499 in the WT simulations. Glu496 also forms a hydrogen bond with Ser449 on an opposing helix (res. Val441-Ser457). In the variant simulations, Gly496 cannot form these salt bridges, which could weaken the secondary structure. Additionally, the loss of the hydrogen bond with Ser449 on the opposite helix can weaken the tertiary structure assembly. Moreover, glycine is an α-helix breaker, and it is seen to weaken the integrity of the helix as the hydrogen bonding between the backbone atoms of Gly496 and Ala493 breaks down. Also, due to its location at the GAP-Ras interface, the interaction of Glu496 with Arg499 and Lys492 might play a role in complex association and stability, which cannot be fully addressed using the SynGAP solvent-only simulations.
c.719A>G	D240G	Likely Pathogenic	PH	Uncertain		1				-12.825	Likely Pathogenic	0.951	Likely Pathogenic	Ambiguous	0.912	Likely Pathogenic	1.85	Ambiguous	0.1	2.72	Destabilizing	2.29	Destabilizing	0.24	Likely Benign	-6.19	Deleterious	0.993	Probably Damaging	0.984	Probably Damaging	5.79	Benign	0.01	Affected			1	-1	3.1	-58.04
c.895C>T	R299C (3D Viewer)	Likely Pathogenic	C2	Conflicting		2	6-33437800-C-T	3	1.86e-6	-6.326	Likely Benign	0.572	Likely Pathogenic	Likely Benign	0.344	Likely Benign	1.85	Ambiguous	0.4	0.61	Ambiguous	1.23	Ambiguous	0.76	Ambiguous	-3.54	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	1.65	Pathogenic	0.06	Tolerated	3.39	19	-4	-3	7.0	-53.05	210.7	91.3	0.1	0.0	0.0	0.2	X	X						Potentially Pathogenic	The guanidinium group of Arg299, located in a β hairpin loop linking two anti-parallel β sheet strands (res. Met289-Pro298, res. Thr305-Asn315), forms hydrogen bonds that stabilize the tight turn. In the WT simulations, the Arg299 side chain hydrogen bonds with the loop backbone carbonyl groups (e.g., Ser302, Thr305, Leu274, Gly303), the hydroxyl group of Ser300, and even forms a salt bridge with the carboxylate group of Asp304.In the variant simulations, the thiol group of the Cys299 side chain is unable to form any of these well-coordinated or strong interactions, which could affect the initial formation of the secondary hairpin loop during folding. β hairpins are potential nucleation sites during the initial stages of protein folding, so even minor changes in them could be significant. Moreover, the positively charged Arg299 side chain faces the polar head group region of the inner leaflet membrane and could directly anchor the C2 domain to the membrane. In short, the residue swap could negatively affect both protein folding and the stability of the SynGAP-membrane association.
c.930G>C	E310D (3D Viewer)	Likely Pathogenic	C2	Likely Pathogenic		1				-11.218	Likely Pathogenic	0.994	Likely Pathogenic	Likely Pathogenic	0.666	Likely Pathogenic	1.87	Ambiguous	0.5	2.39	Destabilizing	2.13	Destabilizing	1.04	Destabilizing	-2.76	Deleterious	0.997	Probably Damaging	0.992	Probably Damaging	1.19	Pathogenic	0.02	Affected	3.38	19	3	2	0.0	-14.03	232.6	27.2	0.1	0.0	0.1	0.1						X		Potentially Benign	The carboxylate group of Glu310, located in an anti-parallel β sheet strand (res. Thr305-Asn315), is ideally positioned to interact with the hydroxyl and backbone amide groups of Thr295 on a twisted anti-parallel β strand. Because the carboxylate group can also interact with the GAP domain residues (e.g., Gln612, Tyr614), Glu310 potentially plays a key role in maintaining the tertiary assembly between the C2 and GAP domains. In the variant simulations, the carboxylate group of Asp310 can form the same interactions as glutamate; however, due to its one hydrocarbon shorter length, the connections are less stable or less optimal.
c.1792C>G	L598V (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-10.002	Likely Pathogenic	0.578	Likely Pathogenic	Likely Benign	0.221	Likely Benign	1.89	Ambiguous	0.1	1.58	Ambiguous	1.74	Ambiguous	1.01	Destabilizing	-2.92	Deleterious	0.944	Possibly Damaging	0.786	Possibly Damaging	3.21	Benign	0.02	Affected	3.37	35	2	1	0.4	-14.03	218.4	29.6	0.0	0.0	0.8	0.0						X		Potentially Benign	The iso-butyl side chain of Leu598, located on an α helix (res. Glu582-Met603), packs hydrophobically with other hydrophobic residues in the inter-helix space (e.g., Ile602, Phe594, Ile510).In the variant simulations, Val598, which has similar size and physicochemical properties to leucine, resides in the inter-helix hydrophobic space in a similar manner to Leu598 in the WT. This causes no negative effects on the protein structure.
c.1045C>T	P349S (3D Viewer)		C2	Uncertain		1				-7.654	In-Between	0.217	Likely Benign	Likely Benign	0.277	Likely Benign	1.92	Ambiguous	0.1	2.28	Destabilizing	2.10	Destabilizing	0.87	Ambiguous	-6.13	Deleterious	1.000	Probably Damaging	0.996	Probably Damaging	1.66	Pathogenic	0.06	Tolerated	3.37	25	1	-1	0.8	-10.04	194.9	-18.1	-0.1	0.0	0.2	0.1	X						X	Potentially Pathogenic	The cyclic pyrrolidine side chain of Pro349, located at the end of an anti-parallel β sheet strand (res. Gly341-Pro349), allows the strand to end and make a tight turn before a short α helical section within a loop connecting to another β strand (res. Thr359-Pro364). In the variant simulations, the hydroxyl group of Ser349 forms a hydrogen bond with the backbone amide group of Ala351 in the short helical section. Conversely, the backbone amide group of Ser349 (absent in proline) does not form any intra-protein hydrogen bonds. However, the β strand end connects to the α helical section in a more stable and consistent manner compared to the WT. Although the residue swap does not cause major adverse effects on the protein structure in the simulations, it is possible that the tight turn at the β strand end could not be created during folding without the presence of proline.
c.1150G>A	G384S (3D Viewer)	Likely Benign	C2	Uncertain		1	6-33438055-G-A	1	6.22e-7	-5.243	Likely Benign	0.090	Likely Benign	Likely Benign	0.315	Likely Benign	1.92	Ambiguous	0.2	1.66	Ambiguous	1.79	Ambiguous	0.19	Likely Benign	-0.67	Neutral	0.980	Probably Damaging	0.968	Probably Damaging	1.33	Pathogenic	0.04	Affected	4.32	2	1	0	-0.4	30.03	202.4	-49.8	0.5	1.0	-0.2	0.0								Uncertain	Gly384 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364, res. Ala399-Ile411). Because the Ω loop is assumed to directly interact with the membrane, it moves arbitrarily throughout the WT solvent simulations. The Ω loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone.Ω loops are known to play major roles in protein functions that require flexibility, and so they are rich in glycines, prolines, and, to a lesser extent, small hydrophilic residues to ensure maximum flexibility. Thus, the variant’s Ser384 is potentially tolerated in the Ω loop, although the hydroxyl group of Ser384 forms various hydrogen bonds with several other loop residues in the variant simulations. However, since the effects on Gly-rich Ω loop dynamics can only be studied through the SynGAP-membrane complex, no definite conclusions can be drawn.
c.1531G>A	G511R (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-11.327	Likely Pathogenic	0.991	Likely Pathogenic	Likely Pathogenic	0.416	Likely Benign	1.94	Ambiguous	0.3	1.32	Ambiguous	1.63	Ambiguous	0.94	Ambiguous	-7.72	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.26	Benign	0.06	Tolerated	3.37	35	-3	-2	-4.1	99.14	279.4	-159.9	0.0	0.0	0.7	0.1			X				X	Potentially Pathogenic	Gly511 is located in an α-helix (res. Gly502-Tyr518), facing hydrophobic residues in an inter-helix space (e.g., Leu610, Ile514) in the WT simulations. In contrast, in the variant simulations, the bulkier and positively charged guanidinium side chain of Arg511 forms a salt bridge with the carboxylate group of Glu217 or hydrogen bonds with the backbone carbonyl group of Leu610. Although the residue swap introduces a third positively charged residue in close vicinity (Arg511, Lys507, Arg515), the protein structure seems to remain stable in the variant simulations. Importantly, according to ClinVar, the residue swap alters the last nucleotide of an exon and is predicted to destroy the splice donor site, resulting in aberrant splicing and pathogenic status.	10.1016/j.ajhg.2020.11.011
c.1531G>C	G511R (3D Viewer)	Likely Pathogenic	GAP	Pathogenic		1				-11.327	Likely Pathogenic	0.991	Likely Pathogenic	Likely Pathogenic	0.415	Likely Benign	1.94	Ambiguous	0.3	1.32	Ambiguous	1.63	Ambiguous	0.94	Ambiguous	-7.72	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.26	Benign	0.06	Tolerated	3.37	35	-3	-2	-4.1	99.14	279.4	-159.9	0.0	0.0	0.7	0.1			X				X	Potentially Pathogenic	Gly511 is located in an α-helix (res. Gly502-Tyr518), facing hydrophobic residues in an inter-helix space (e.g., Leu610, Ile514) in the WT simulations. In contrast, in the variant simulations, the bulkier and positively charged guanidinium side chain of Arg511 forms a salt bridge with the carboxylate group of Glu217 or hydrogen bonds with the backbone carbonyl group of Leu610. Although the residue swap introduces a third positively charged residue in close vicinity (Arg511, Lys507, Arg515), the protein structure seems to remain stable in the variant simulations. Importantly, according to ClinVar, the residue swap alters the last nucleotide of an exon and is predicted to destroy the splice donor site, resulting in aberrant splicing and pathogenic status.	10.1016/j.ajhg.2020.11.011
c.775C>T	R259W (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-12.186	Likely Pathogenic	0.985	Likely Pathogenic	Likely Pathogenic	0.691	Likely Pathogenic	1.95	Ambiguous	0.8	0.51	Ambiguous	1.23	Ambiguous	0.51	Ambiguous	-7.35	Deleterious	1.000	Probably Damaging	0.993	Probably Damaging	5.76	Benign	0.00	Affected	3.39	15	2	-3	3.6	30.03	254.0	40.0	0.2	0.2	0.2	0.4	X	X					X	Potentially Pathogenic	The guanidinium group of Arg259, located at the beginning of an anti-parallel β sheet strand (res. Arg259-Arg272), forms salt bridges with the carboxylate groups of Asp684 at the end of an α helix (res. Ile683-Gln702, GAP domain) and Asp261 on the same β strand. The Arg259 side chain also frequently forms hydrogen bonds with the backbone carbonyl groups of Ser257, Asn256, and Asp255. In the variant simulations, the indole ring of the Trp259 side chain cannot form salt bridges or maintain hydrogen bonding with the carboxylate group of Asp684 or other nearby residues. Notably, the amino group of the Lys254 side chain maintains a salt bridge with Asp684 and Glu244 throughout the variant simulations, while it forms a cation-π bond with the indole ring of Trp259 in the variant. This salt bridge is not maintained in the WT simulations. Additionally, the partially or loosely α helical conformation of a lysine-containing loop (res. Lys251-Ser257), which extends to a nearby α helix (res. Met414-Asn426), could be stabilized due to the residue swap. Moreover, the bulky size of the Trp259 side chain requires nearby residues to adjust their positioning to accommodate the introduced residue, weakening the tertiary structure assembly between the C2, PH, and GAP domains. The residue swap potentially causes more severe effects during protein folding or for the SynGAP-membrane interaction than the solvent-only simulations imply.
c.928G>A	E310K (3D Viewer)	Likely Pathogenic	C2	Conflicting		4				-14.601	Likely Pathogenic	0.997	Likely Pathogenic	Likely Pathogenic	0.764	Likely Pathogenic	1.97	Ambiguous	1.2	3.66	Destabilizing	2.82	Destabilizing	1.02	Destabilizing	-3.68	Deleterious	1.000	Probably Damaging	0.995	Probably Damaging	1.19	Pathogenic	0.01	Affected	3.38	19	0	1	-0.4	-0.94	213.4	58.0	0.1	0.0	0.2	0.1		X						Potentially Pathogenic	The carboxylate group of Glu310, located in an anti-parallel β sheet strand (res. Thr305-Asn315), is ideally positioned to interact with the side chain hydroxyl and backbone amide groups of Thr295 on a twisted anti-parallel β strand (res. Met289-Arg299). Because the carboxylate group can also interact with the GAP domain residues (e.g., Gln612, Tyr614), Glu310 plays a key role in maintaining the tertiary assembly between the C2 and GAP domains. In the variant simulations, the amino group of the Lys310 side chain hydrogen bonds with the GAP domain residues and forms a salt bridge with Glu613. Although no apparent negative effects are seen due to the residue swap, it is possible that the loss of hydrogen bonding with the hydroxyl group of the Thr295 side chain causes problems during folding, potentially compromising the twisting of the β sheet.
c.1832T>C	M611T (3D Viewer)	Likely Benign	GAP	Uncertain		1	6-33440884-T-C	1	6.19e-7	-5.696	Likely Benign	0.101	Likely Benign	Likely Benign	0.240	Likely Benign	1.98	Ambiguous	0.2	0.94	Ambiguous	1.46	Ambiguous	0.87	Ambiguous	-2.40	Neutral	0.034	Benign	0.038	Benign	-1.19	Pathogenic	0.29	Tolerated	3.37	35	-1	-1	-2.6	-30.09
c.835C>T	R279W (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-11.417	Likely Pathogenic	0.942	Likely Pathogenic	Ambiguous	0.485	Likely Benign	2.00	Destabilizing	0.8	1.47	Ambiguous	1.74	Ambiguous	0.80	Ambiguous	-6.29	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	1.88	Pathogenic	0.00	Affected	3.39	18	2	-3	3.6	30.03	270.0	38.3	0.1	0.0	0.3	0.0								Uncertain	The guanidinium group of Arg279, located at the beginning of an anti-parallel β sheet strand (res. Arg279-Leu286), can form hydrogen bond with the backbone carbonyl groups of nearby loop residues (e.g., Ser296, Ser331, and As332) and form salt bridges with the carboxylate groups of Asp330 and Asp332. In the WT simulations, Arg279 sporadically forms a salt bridge even with the carboxylate group of Glu613, loosely connecting the C2 domain and GAP domain. Meanwhile, the indole ring of the Trp279 side chain is unable to hydrogen bond with the loop residues in the variant simulations. The lack of hydrogen bond or salt bridge formation with the loop residues could be significant, as Arg279 and the loops face the polar head group region of the membrane. Thus, although Trp279 could interact with the membrane surface as a “lipid anchor,” any changes to the wider loop dynamics could still adversely affect the formation of a stable SynGAP-membrane association. However, no definite conclusions on the effect of the residue swap on the SynGAP-membrane association can be drawn from solvent-only simulations.
c.1784T>C	L595P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-11.856	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.747	Likely Pathogenic	2.09	Destabilizing	0.8	5.88	Destabilizing	3.99	Destabilizing	1.78	Destabilizing	-6.97	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.72	Benign	0.00	Affected	3.37	35	-3	-3	-5.4	-16.04
c.1304T>G	L435W (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.889	Likely Pathogenic	0.992	Likely Pathogenic	Likely Pathogenic	0.572	Likely Pathogenic	2.11	Destabilizing	0.1	0.69	Ambiguous	1.40	Ambiguous	1.66	Destabilizing	-5.63	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	3.15	Benign	0.00	Affected	3.37	29	-2	-2	-4.7	73.05	242.2	-25.2	0.0	0.0	0.3	0.1							X	Potentially Pathogenic	The iso-butyl side chain of Leu435, located in an α helix (res. Met414-Glu436), packs against other hydrophobic residues in an interhelix space (e.g., Val699, Val447, Leu489, Leu439) in the WT simulations. In the variant simulations, the indole ring of Trp435 fits into the same niche despite its considerably bulkier size. Additionally, the side chain forms an H-bond with the backbone carbonyl of Leu696 in an α helix (res. Asp684-Gln702). Although no apparent negative changes are observed during the variant simulation, the size difference between the swapped residues could affect the protein folding process.
c.1405G>A	A469T (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-9.540	Likely Pathogenic	0.723	Likely Pathogenic	Likely Benign	0.527	Likely Pathogenic	2.26	Destabilizing	0.1	1.90	Ambiguous	2.08	Destabilizing	0.34	Likely Benign	-1.46	Neutral	0.994	Probably Damaging	0.986	Probably Damaging	-1.21	Pathogenic	0.42	Tolerated			1	0	-2.5	30.03
c.1718G>A	R573Q (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-9.900	Likely Pathogenic	0.923	Likely Pathogenic	Ambiguous	0.733	Likely Pathogenic	2.28	Destabilizing	0.8	1.94	Ambiguous	2.11	Destabilizing	1.08	Destabilizing	-3.16	Deleterious	1.000	Probably Damaging	0.995	Probably Damaging	-1.31	Pathogenic	0.12	Tolerated	3.37	35	1	1	1.0	-28.06	230.1	49.9	0.0	0.0	-0.6	0.0	X	X						Potentially Pathogenic	The guanidinium group of Arg573, located in an α-helix (res. Arg563-Glu578), forms a salt bridge with the carboxylate groups of Glu582 and/or Asp586 from a nearby α-helix (res. Glu582-Met603) in the WT simulations. Additionally, the Arg573 side chain stacks planarly with the aromatic phenol ring of Tyr665 and hydrogen bonds with the hydroxyl group of Ser668 from another α-helix (res. Ser641-Ser668). In the variant simulations, although the carboxamide group of the Gln573 side chain can hydrogen bond with the carboxylate group of Glu582 or the hydroxyl group of Ser668, these interactions are not as coordinated, stable, or strong as those of the positively charged Arg573. Consequently, the integrity of the opposing α-helix end (res. Glu582-Met603) is weakened. Overall, the residue swap has the potential to substantially affect the tertiary structure assembly during the protein folding process.
c.1540A>T	I514F (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-13.383	Likely Pathogenic	0.962	Likely Pathogenic	Likely Pathogenic	0.601	Likely Pathogenic	2.35	Destabilizing	0.3	3.74	Destabilizing	3.05	Destabilizing	0.93	Ambiguous	-3.98	Deleterious	0.997	Probably Damaging	0.993	Probably Damaging	2.89	Benign	0.00	Affected	3.37	35	0	1	-1.7	34.02
c.2086C>G	L696V (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-11.909	Likely Pathogenic	0.745	Likely Pathogenic	Likely Benign	0.351	Likely Benign	2.35	Destabilizing	0.1	1.85	Ambiguous	2.10	Destabilizing	1.46	Destabilizing	-2.79	Deleterious	0.992	Probably Damaging	0.970	Probably Damaging	3.16	Benign	0.00	Affected	3.46	13	1	2	0.4	-14.03
c.1717C>T	R573W (3D Viewer)	Likely Pathogenic	GAP	Conflicting		8				-14.078	Likely Pathogenic	0.995	Likely Pathogenic	Likely Pathogenic	0.758	Likely Pathogenic	2.37	Destabilizing	0.7	0.57	Ambiguous	1.47	Ambiguous	0.88	Ambiguous	-6.94	Deleterious	1.000	Probably Damaging	0.997	Probably Damaging	-1.48	Pathogenic	0.00	Affected	3.37	35	2	-3	3.6	30.03	257.6	39.0	0.1	0.0	0.2	0.0	X	X						Potentially Pathogenic	The guanidinium group of Arg573, located in an α-helix (res. Arg563-Glu578), forms a salt bridge with the carboxylate groups of Glu582 and/or Asp586 from a nearby α-helix (res. Glu582-Met603) in the WT simulations. Additionally, the Arg573 side chain stacks planarly with the aromatic phenol ring of Tyr665 and hydrogen bonds with the hydroxyl group of Ser668 from another α-helix (res. Ser641-Ser668). In the variant simulations, the indole ring of the Trp573 side chain is unable to maintain the same level of coordination as the positively charged Arg573 side chain. Indeed, Trp573 is seen hydrogen bonding only briefly with the carboxylate group of Glu582. Consequently, the integrity of the opposing α-helix end (res. Glu582-Met603) is weakened. Overall, the residue swap has the potential to substantially affect the tertiary structure assembly during the protein folding process.
c.929A>G	E310G (3D Viewer)	Likely Pathogenic	C2	Pathogenic		1				-14.132	Likely Pathogenic	0.995	Likely Pathogenic	Likely Pathogenic	0.848	Likely Pathogenic	2.38	Destabilizing	0.7	3.56	Destabilizing	2.97	Destabilizing	0.36	Likely Benign	-6.43	Deleterious	1.000	Probably Damaging	0.996	Probably Damaging	1.12	Pathogenic	0.00	Affected	3.38	19	-2	0	3.1	-72.06
c.1552T>C	Y518H (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-9.797	Likely Pathogenic	0.943	Likely Pathogenic	Ambiguous	0.496	Likely Benign	2.39	Destabilizing	0.4	0.82	Ambiguous	1.61	Ambiguous	1.31	Destabilizing	-4.74	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.40	Benign	0.08	Tolerated			0	2	-1.9	-26.03
c.1502T>C	I501T (3D Viewer)	Likely Benign	GAP	Uncertain		1				-5.996	Likely Benign	0.252	Likely Benign	Likely Benign	0.362	Likely Benign	2.40	Destabilizing	0.1	1.81	Ambiguous	2.11	Destabilizing	1.57	Destabilizing	-3.48	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.44	Benign	0.16	Tolerated	3.37	35	0	-1	-5.2	-12.05	214.5	26.9	0.0	0.0	0.5	0.0							X	Potentially Pathogenic	Ile501 is located near a hinge in the middle of an α-helix (res. Leu489-Glu519). The sec-butyl side chain of Ile501 is hydrophobically packed with other residues in the inter-helix space (e.g., Leu500, Tyr497, Phe679) in the WT simulations. In the variant simulations, the hydroxyl group of Thr501 forms a hydrogen bond with the backbone atoms of Tyr497 on the same α-helix, which may weaken the α-helix integrity. Additionally, the polar hydroxyl group of Thr501 is not suitable for the hydrophobic inter-helix space, and thus, the residue swap could affect protein folding. However, Ile501 is followed by Gly502, which facilitates a hinge in the middle of the α-helix, making further weakening caused by Thr501 unlikely to be harmful to the α-helix integrity.
c.1947G>C	M649I (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-9.361	Likely Pathogenic	0.995	Likely Pathogenic	Likely Pathogenic	0.449	Likely Benign	2.42	Destabilizing	0.2	1.96	Ambiguous	2.19	Destabilizing	1.01	Destabilizing	-3.99	Deleterious	0.672	Possibly Damaging	0.093	Benign	3.40	Benign	0.02	Affected	3.38	27	2	1	2.6	-18.03	243.7	21.5	0.0	0.1	0.0	0.1							X	Potentially Benign	The thioether side chain of Met649, located on an α helix (res. Ser641-Glu666), bridges Phe652, Phe648, and Phe639 in an inter-helix hydrophobic cavity in the WT simulations. In the variant simulations, the sec-butyl side chain of Ile649 maintains hydrophobic interactions with nearby residues, with no significant effects on the protein structure.However, methionine is known as a bridging motif for aromatic residues, and these Met-aromatic interactions are lost in the variant. Indeed, in the second variant simulation,the bridging of Phe652, Phe648 and Phe639 is completely lost. In reality, the effect could be more severe on the structure during the protein folding.
c.1393C>G	L465V (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-9.893	Likely Pathogenic	0.838	Likely Pathogenic	Ambiguous	0.276	Likely Benign	2.46	Destabilizing	0.1	2.66	Destabilizing	2.56	Destabilizing	1.21	Destabilizing	-2.98	Deleterious	0.996	Probably Damaging	0.992	Probably Damaging	2.44	Pathogenic	0.10	Tolerated	3.37	34	2	1	0.4	-14.03	204.3	30.9	0.0	0.0	-0.4	0.6						X		Potentially Benign	The iso-butyl side chain of Leu465, located in the middle of an α helix (res. Ala461–Phe476), packs with hydrophobic residues (e.g., Phe464, Met468, Tyr497, Ile494) in an inter-helix space formed with two other α helices (res. Ala461–Phe476 and res. Thr488-Gly502). In the variant simulations, the iso-propyl side chain of Val465 is equally sized and similarly hydrophobic as the original side chain of Leu465. Hence, the mutation does not exert any negative effects on the protein structure based on the variant simulations.
c.1621G>C	A541P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.733	Likely Pathogenic	0.996	Likely Pathogenic	Likely Pathogenic	0.594	Likely Pathogenic	2.47	Destabilizing	0.3	7.26	Destabilizing	4.87	Destabilizing	0.86	Ambiguous	-3.16	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	-1.34	Pathogenic	0.07	Tolerated	3.37	35	1	-1	-3.4	26.04	170.4	-11.2	0.1	0.0	0.1	0.0	X							Potentially Pathogenic	Ala541 is located on the outer surface of an α-helix (res. Ala533-Val560). The methyl group of Ala541 is on the surface and does not form any interactions. Proline lacks a free backbone amide group, and thus, Pro541 is unable to form a hydrogen bond with the carbonyl group of Ala537 in the variant simulations. Consequently, Pro541 disrupts the continuity of the secondary structure element, causing the α-helix to bend slightly in the variant simulations.
c.1025A>G	Y342C (3D Viewer)	Likely Pathogenic	C2	Benign/Likely benign		2	6-33437930-A-G	21	1.30e-5	-7.596	In-Between	0.682	Likely Pathogenic	Likely Benign	0.404	Likely Benign	2.48	Destabilizing	0.1	2.73	Destabilizing	2.61	Destabilizing	0.92	Ambiguous	-6.67	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	1.72	Pathogenic	0.02	Affected	3.37	25	0	-2	3.8	-60.04	242.4	62.8	0.1	0.0	-0.1	0.2								Potentially Pathogenic	The phenol ring of Tyr342, located at the end of an anti-parallel β sheet strand (res. Gly341-Pro349), faces outward in the C2 domain. This phenol ring contributes to a triple tyrosine stack (Tyr342, Tyr328, and Tyr281) that links together three anti-parallel β sheet strands. Additionally, it shields Gly344 from the solvent, reducing its exposure and providing stability for the β-sandwich. This motif also contributes to a twist formation in the β sheet.In the variant simulations, the Cys342 side chain cannot participate in the stack formation. Instead, its thiol group forms a hydrogen bond with the backbone carbonyl group of Leu327. Although these changes in surface interactions could weaken the characteristic twist that strengthens the β sheet fold, no major structural effects are observed in the variant simulations. The residue swap could also affect the SynGAP-membrane association; however, this phenomenon cannot be addressed using solvent-only simulations. Notably, the thiol group of cysteine is not a particularly strong hydrogen-bonding partner, which could mitigate the negative effects of the residue swap.
c.1466T>C	L489P (3D Viewer)	Likely Pathogenic	GAP	Conflicting		2				-13.520	Likely Pathogenic	0.997	Likely Pathogenic	Likely Pathogenic	0.939	Likely Pathogenic	2.50	Destabilizing	0.1	4.69	Destabilizing	3.60	Destabilizing	1.73	Destabilizing	-6.74	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.56	Pathogenic	0.00	Affected	3.37	35	-3	-3	-5.4	-16.04	209.9	61.9	0.1	0.0	0.6	0.1		X						Potentially Pathogenic	The iso-butyl side chain of Leu489, located in the α-helix (res. Leu489-Glu519) within an inter-helix space of four helices (res. Ala461-Phe476, res. Val441-Ser457, and res. Met414-Glu436), packs with hydrophobic residues (e.g., Cys432, Ala448, Lys444, Ala493, Val447, Met468). In the variant simulations, Pro489 is located near the beginning of the α-helix, so the residue swap with Leu489 does not affect the continuity of the secondary structure element. However, the side chain of proline is not as optimal as that of leucine for maintaining hydrophobic packing with nearby residues (e.g., Ala448, Lys444). Additionally, the consistently maintained hydrogen bond interaction between the backbone amide group of Leu489 and the carbonyl of Glu436 is lost due to the residue swap, potentially affecting the tertiary structure integrity.
c.1778T>A	L593H (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-16.504	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.812	Likely Pathogenic	2.52	Destabilizing	0.2	2.32	Destabilizing	2.42	Destabilizing	2.75	Destabilizing	-6.77	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.77	Benign	0.00	Affected	3.37	35	-2	-3	-7.0	23.98	222.0	20.7	0.0	0.0	0.2	0.0		X					X	Potentially Pathogenic	The iso-propyl side chain of Leu593, located in an α helix (res. Glu582-Met603), packs favourably with multiple hydrophobic residues in the inter-helix space (e.g., Leu598, Ile589, Phe594, Phe561).In the variant simulations, His593 retains a similar packing arrangement via its aromatic imidazole ring. However, the polar nitrogen atoms introduce hydrogen bond donors and acceptors into the previously hydrophobic space. The epsilon protonated nitrogen of His593 forms a stable hydrogen bond with the phenol group of the Tyr505 side chain in an α helix (res. Gln503-Tyr518).While the residue swap could affect the tertiary assembly and the underlying protein folding process, it is difficult to determine if the mutation would be tolerated based solely on the variant simulations.
c.1404G>A	M468I (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1	6-33438436-G-A	1	6.20e-7	-8.583	Likely Pathogenic	0.907	Likely Pathogenic	Ambiguous	0.508	Likely Pathogenic	2.53	Destabilizing	0.2	1.89	Ambiguous	2.21	Destabilizing	0.37	Likely Benign	-1.06	Neutral	0.748	Possibly Damaging	0.886	Possibly Damaging	-1.10	Pathogenic	0.07	Tolerated	3.37	31	1	2	2.6	-18.03
c.986G>A	R329H (3D Viewer)	Likely Pathogenic	C2	Uncertain		1	6-33437891-G-A	2	1.24e-6	-10.154	Likely Pathogenic	0.769	Likely Pathogenic	Likely Benign	0.155	Likely Benign	2.53	Destabilizing	0.7	0.71	Ambiguous	1.62	Ambiguous	0.82	Ambiguous	-3.17	Deleterious	0.995	Probably Damaging	0.778	Possibly Damaging	4.04	Benign	0.05	Affected	3.41	15	2	0	1.3	-19.05	220.4	81.4	0.1	0.1	0.2	0.3								Uncertain	The guanidinium group of Arg329, located at the end of an anti-parallel β sheet strand (res. Ala322-Asp330), faces the negatively charged lipid bilayer surface. While the residue swap does not cause any apparent negative effects on the protein structure in the variant simulations, it could adversely affect the SynGAP-membrane association in reality. The positively charged Arg329 side chain forms hydrogen bonds with other loop residues (e.g., Ser371, Asp338) that are expected to dynamically interact with the membrane head group region. However, this phenomenon is beyond the scope of the solvent-only simulations to unravel. Notably, histidine can also be double protonated and positively charged, but this alternative protonation state was not considered in the variant simulations.
c.821T>A	L274Q (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-15.518	Likely Pathogenic	0.995	Likely Pathogenic	Likely Pathogenic	0.774	Likely Pathogenic	2.54	Destabilizing	0.3	1.74	Ambiguous	2.14	Destabilizing	1.97	Destabilizing	-5.42	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	0.00	Pathogenic	0.00	Affected	3.38	19	-2	-2	-7.3	14.97	245.9	1.8	0.0	0.0	0.1	0.2	X		X				X	Potentially Pathogenic	The aliphatic side chain of Leu274, located in a β hairpin loop (res. Glu273-Lys278) connecting two anti-parallel β sheet strands, packs against multiple hydrophobic residues facing the β sheet (e.g., Ala271, Leu327, Tyr280, Val306). The hydrophilic carboxamide group of the Gln274 side chain is not suitable for this hydrophobic niche, causing nearby residues to adjust to make room for the hydrophilic glutamine. Additionally, a new hydrogen bond forms with the backbone carboxyl group of Arg272 in another β strand (res. Glu273-Arg259).As a result, the backbone amide group of Ala399 and the carbonyl group of Arg272, which connect two β strands at the β sheet end, form fewer hydrogen bonds in the variant than in the WT simulations. Although no major secondary structure disruption is observed in the variant simulations, the residue swap could profoundly affect the C2 domain folding, as the hydrophobic packing of Leu274 is crucial for maintaining the loop's contact with the rest of the C2 domain. Lastly, because the Leu274-containing loop faces the membrane surface, the residue swap could also negatively impact the SynGAP-membrane association.
c.1126G>T	G376C		C2	Uncertain		1				-7.686	In-Between	0.125	Likely Benign	Likely Benign	0.560	Likely Pathogenic	2.56	Destabilizing	0.5	0.22	Likely Benign	1.39	Ambiguous	0.16	Likely Benign	-1.15	Neutral	1.000	Probably Damaging	1.000	Probably Damaging	1.32	Pathogenic	0.01	Affected			-3	-3	2.9	46.09
c.680G>A	G227E (3D Viewer)	Likely Pathogenic	PH	Conflicting		2	6-33435531-G-A	3	1.86e-6	-9.186	Likely Pathogenic	0.996	Likely Pathogenic	Likely Pathogenic	0.792	Likely Pathogenic	2.56	Destabilizing	0.4	5.36	Destabilizing	3.96	Destabilizing	0.94	Ambiguous	-6.49	Deleterious	0.906	Possibly Damaging	0.360	Benign	5.72	Benign	0.01	Affected	3.43	12	0	-2	-3.1	72.06	237.7	-112.1	0.1	0.3	0.0	0.3		X				X		Uncertain	The introduced residue Glu227 is located in a β hairpin loop connecting two anti-parallel β sheet strands (res. Cys219-Thr224 and Thr228-Ala232). In the variant simulations, the carboxylate group of Glu227 frequently forms a salt bridge with the amino group of the neighboring residue Lys229. Despite this interaction, the integrity of the secondary structure element is not compromised. However, the β hairpins are potential nucleation sites during the initial stages of protein folding. Additionally, since the model ends abruptly at the N-terminus, no definite conclusions can be drawn from the simulations.
c.1169G>A	G390E (3D Viewer)		C2	Uncertain		1				-7.913	In-Between	0.646	Likely Pathogenic	Likely Benign	0.575	Likely Pathogenic	2.61	Destabilizing	0.9	4.28	Destabilizing	3.45	Destabilizing	0.47	Likely Benign	-0.87	Neutral	0.276	Benign	0.045	Benign	1.32	Pathogenic	0.05	Affected	4.32	8	0	-2	-3.1	72.06	241.5	-108.4	0.6	0.5	-0.1	0.1								Uncertain	Gly390 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364 and res. Ala399-Ile411). The Ω loop is assumed to directly interact with the membrane, and it is observed to move arbitrarily throughout the WT solvent simulations. This loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone.Ω loops are known to play significant roles in protein functions that require flexibility, and so they are rich in glycine residues, prolines, and to a lesser extent, small hydrophilic residues to ensure maximum flexibility. Thus, the variant’s Glu390 may not be as well tolerated in the Ω loop. Additionally, the carboxylate group of Glu390 occasionally forms H-bonds with other loop residues in the variant simulations. The interaction between the acidic carboxylate side chain and the acidic membrane lipids may further influence the SynGAP-membrane complex. However, since the effects on the Gly-rich Ω loop dynamics can only be well studied through the SynGAP-membrane complex, no definite conclusions can be drawn.
c.1084T>C	W362R (3D Viewer)	Likely Pathogenic	C2	Pathogenic		2				-14.004	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.706	Likely Pathogenic	2.64	Destabilizing	0.3	3.90	Destabilizing	3.27	Destabilizing	1.10	Destabilizing	-12.87	Deleterious	0.999	Probably Damaging	0.996	Probably Damaging	1.28	Pathogenic	0.00	Affected	3.39	24	2	-3	-3.6	-30.03	287.5	-34.1	-0.2	0.1	-0.6	0.2	X			X			X	Potentially Pathogenic	The indole ring of Trp362, located on the surface of an anti-parallel β sheet (res. Thr359-Pro364) in the C2 domain, stacks with nearby residues (e.g., Arg401, Arg272). In the variant simulations, the guanidinium group of the introduced residue Arg362 forms a salt bridge with the carboxylate group of Glu273 and, like Trp362, stacks with other arginine residues (e.g., Arg401, Arg272). This residue is at both the C2-membrane interface and the C2-RasGTPase interface, so the residue swap could potentially affect both interactions. However, these phenomena cannot be addressed using solvent-only simulations. Notably, Arg272, which stacks with both the non-mutated Trp362 and the mutated Arg362, forms a salt bridge directly with Asp105 of Ras in the WT simulations. Therefore, the residue swap could affect the C2 domain stability, the SynGAP-membrane association, and the SynGAP-Ras association.	10.1016/j.ajhg.2020.11.011
c.1402A>G	M468V (3D Viewer)		GAP	Uncertain		1				-9.461	Likely Pathogenic	0.361	Ambiguous	Likely Benign	0.570	Likely Pathogenic	2.69	Destabilizing	0.1	2.20	Destabilizing	2.45	Destabilizing	0.89	Ambiguous	-1.66	Neutral	0.998	Probably Damaging	0.993	Probably Damaging	-1.21	Pathogenic	0.08	Tolerated	3.37	31	1	2	2.3	-32.06
c.1942T>C	F648L	Likely Pathogenic	GAP	Uncertain		1				-9.296	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.468	Likely Benign	2.71	Destabilizing	0.8	2.08	Destabilizing	2.40	Destabilizing	1.04	Destabilizing	-5.98	Deleterious	0.999	Probably Damaging	0.976	Probably Damaging	3.45	Benign	0.08	Tolerated			2	0	1.0	-34.02
c.1408A>G	M470V (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-8.856	Likely Pathogenic	0.478	Ambiguous	Likely Benign	0.770	Likely Pathogenic	2.73	Destabilizing	0.1	1.88	Ambiguous	2.31	Destabilizing	1.31	Destabilizing	-3.58	Deleterious	0.999	Probably Damaging	0.993	Probably Damaging	-1.20	Pathogenic	0.15	Tolerated	3.37	34	1	2	2.3	-32.06
c.1971G>C	W657C	Likely Pathogenic	GAP	Uncertain		1				-12.035	Likely Pathogenic	0.997	Likely Pathogenic	Likely Pathogenic	0.463	Likely Benign	2.74	Destabilizing	0.3	1.69	Ambiguous	2.22	Destabilizing	1.30	Destabilizing	-11.06	Deleterious	1.000	Probably Damaging	0.982	Probably Damaging	3.43	Benign	0.03	Affected			-8	-2	3.4	-83.07
c.1214G>A	R405H (3D Viewer)	Likely Pathogenic	C2	Conflicting		2	6-33438119-G-A	4	2.48e-6	-9.081	Likely Pathogenic	0.706	Likely Pathogenic	Likely Benign	0.371	Likely Benign	2.79	Destabilizing	0.6	1.85	Ambiguous	2.32	Destabilizing	1.26	Destabilizing	-4.54	Deleterious	1.000	Probably Damaging	0.991	Probably Damaging	3.65	Benign	0.01	Affected	3.38	28	2	0	1.3	-19.05	214.0	102.2	-0.1	0.0	-0.7	0.1		X						Potentially Pathogenic	The guanidinium group of Arg405, located in an anti-parallel β sheet strand of the C2 domain (res. Pro398-Ile411), forms a salt bridge with the carboxylate group of the Glu446 side chain from an opposing α helix (res. Val441-Ser457) in the GAP domain. The positively charged Arg405 side chain also stacks with the aromatic ring of the Phe358 side chain from a loop preceding the β strand (res. Thr359-Thr366), which could assist in maintaining the anti-parallel strand arrangement.In the variant simulations, the imidazole ring of His405 does not stack with the aromatic ring of Phe358 nor form any lasting H-bonds with the loop residues. The imidazole ring of His405 (neutral and epsilon protonated in the simulations) is unable to form a salt bridge with Glu446, which could affect the tertiary structure assembly, although this is not apparent based on the variant simulations.
c.1108G>A	G370S (3D Viewer)	Likely Benign	C2	Uncertain		1	6-33438013-G-A	15	9.31e-6	-3.533	Likely Benign	0.081	Likely Benign	Likely Benign	0.282	Likely Benign	2.83	Destabilizing	2.0	1.05	Ambiguous	1.94	Ambiguous	-0.02	Likely Benign	0.47	Neutral	0.000	Benign	0.000	Benign	1.33	Pathogenic	0.77	Tolerated	3.42	19	1	0	-0.4	30.03	196.6	-49.6	0.9	2.2	-0.1	0.4								Uncertain	Gly370 is located in the Gly-rich Ω loop (res. Pro364- Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364, res. Ala399-Ile411). Because, the Ω loop is assumed to be directly interacting with the membrane, it is only seen to move arbitrarily throughout the WT solvent simulations. The Ω loop is potentially playing a crucial loop in the SynGAP-membrane complex association, stability and dynamics, regardless, this aspect cannot be addressed through the solvent simulations only. The Ω-loops are known to have a major role in protein functions that requires flexibility and thus, they are rich in glycines, prolines and to a lesser extent, hydrophilic residues to ensure maximum flexibility. Thus, Ser370 in the variant is potentially tolerated in the Ω loop. However, since the effect on the Gly-rich Ω loop dynamics can only be well-studied through the SynGAP-membrane complex, no definite conclusions can be withdrawn.
c.1738G>A	G580S (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1	6-33440790-G-A	1	6.20e-7	-10.788	Likely Pathogenic	0.861	Likely Pathogenic	Ambiguous	0.644	Likely Pathogenic	2.84	Destabilizing	0.2	0.59	Ambiguous	1.72	Ambiguous	0.87	Ambiguous	-5.73	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	-1.23	Pathogenic	0.07	Tolerated	3.37	34	1	0	-0.4	30.03	233.9	-49.3	0.8	0.0	0.6	0.1						X		Potentially Benign	Gly580 is located on the outer surface in a short α-α loop turn connecting two α-helices (res. Arg563-Glu578, res. Glu582-Phe608) in the WT simulations. In the variant simulations, the side chain of Ser580 faces outward, and its hydroxyl group does not make any new or additional interactions compared to Gly580 in the WT simulations that could affect the protein structure.
c.1436G>C	R479P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-11.795	Likely Pathogenic	0.938	Likely Pathogenic	Ambiguous	0.277	Likely Benign	2.86	Destabilizing	0.2	3.88	Destabilizing	3.37	Destabilizing	0.81	Ambiguous	-3.52	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.41	Benign	0.18	Tolerated			0	-2	2.9	-59.07
c.872A>G	Y291C (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-8.997	Likely Pathogenic	0.967	Likely Pathogenic	Likely Pathogenic	0.505	Likely Pathogenic	2.90	Destabilizing	0.4	3.51	Destabilizing	3.21	Destabilizing	1.35	Destabilizing	-7.37	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	1.76	Pathogenic	0.01	Affected	3.38	23	0	-2	3.8	-60.04	205.2	66.1	0.1	0.0	-0.4	0.4	X						X	Potentially Pathogenic	The phenol group of the Tyr291 side chain, located in an anti-parallel β sheet strand (res. Met289-Pro298), packs against hydrophobic residues of the C2 and PH domains (e.g., Leu317, Leu286, Leu284, Pro208, Val209). The phenol ring of Tyr291 also forms favorable Met-aromatic stacking with the methyl group of Met289. In the variant simulation, the thiol group of the Cys291 side chain is not as suitable for the hydrophobic inter-domain space as the phenol ring of Tyr291. Consequently, the structural unity of the PH domain is weakened and ultimately unfolds in the second simulation. Moreover, the residue swap might result in severe detrimental effects on the C2 domain structure and the C2-PH domain tertiary structure assembly during folding.
c.1513T>C	Y505H (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-11.383	Likely Pathogenic	0.982	Likely Pathogenic	Likely Pathogenic	0.646	Likely Pathogenic	2.91	Destabilizing	0.1	2.88	Destabilizing	2.90	Destabilizing	1.60	Destabilizing	-4.97	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.64	Benign	0.00	Affected	3.37	35	2	0	-1.9	-26.03
c.1877T>C	I626T	Likely Pathogenic	GAP	Uncertain		1				-10.420	Likely Pathogenic	0.946	Likely Pathogenic	Ambiguous	0.640	Likely Pathogenic	2.94	Destabilizing	0.1	2.70	Destabilizing	2.82	Destabilizing	2.23	Destabilizing	-4.18	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.04	Benign	0.00	Affected			0	-1	-5.2	-12.05
c.1786C>T	R596C (3D Viewer)	Likely Pathogenic	GAP	Conflicting		2	6-33440838-C-T	6	3.72e-6	-10.805	Likely Pathogenic	0.972	Likely Pathogenic	Likely Pathogenic	0.633	Likely Pathogenic	2.94	Destabilizing	0.0	1.49	Ambiguous	2.22	Destabilizing	-0.03	Likely Benign	-7.96	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.41	Pathogenic	0.00	Affected	3.37	35	-4	-3	7.0	-53.05	230.7	97.9	-0.1	0.0	-0.3	0.4		X		X				Potentially Pathogenic	The guanidinium group of Arg596, located in an α helix (res. Glu582-Met603), forms a salt bridge with the carboxylate group of Glu495 from another α helix (res. Leu489-Glu519). In the WT simulations, the side chain of Arg596 hydrogen bonds with the backbone carbonyl groups of Asn487, Glu486, Arg485, and Phe484. Additionally, Arg596 can hydrogen bond with the carboxamide group of the Asn487 side chain on an opposing loop that links two α helices (res. Ala461-Arg475, res. Leu489-Glu519).In the variant simulations, the thiol group of the Cys596 side chain is unable to form salt bridges or any of the hydrogen bonds that the Arg596 side chain can. Thus, the residue swap could affect the tertiary structure assembly more profoundly than observed in the simulations. Notably, Arg596 plays a key role in positioning the aforementioned loop, which is crucial for the placement of the “arginine finger” or the Arg485 side chain during RasGTPase activation.
c.1787G>A	R596H (3D Viewer)	Likely Pathogenic	GAP	Likely Benign		1	6-33440839-G-A	15	9.29e-6	-11.128	Likely Pathogenic	0.950	Likely Pathogenic	Ambiguous	0.717	Likely Pathogenic	3.00	Destabilizing	0.9	0.43	Likely Benign	1.72	Ambiguous	1.35	Destabilizing	-4.97	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	2.43	Pathogenic	0.00	Affected	3.37	35	2	0	1.3	-19.05	223.5	80.5	-0.1	0.0	-0.1	0.3		X		X				Potentially Pathogenic	The guanidinium group of Arg596, located in an α helix (res. Glu582-Met603), forms a salt bridge with the carboxylate group of Glu495 from another α helix (res. Leu489-Glu519). In the WT simulations, the side chain of Arg596 hydrogen bonds with the backbone carbonyl groups of Asn487, Glu486, Arg485, and Phe484. Additionally, Arg596 can hydrogen bond with the carboxamide group of the Asn487 side chain on an opposing loop that links two α helices (res. Ala461-Arg475, res. Leu489-Glu519).In the variant simulations, the imidazole ring of His596 can form hydrogen bonds with the same residues as arginine; however, these interactions are not as coordinated or strong in comparison. Thus, the residue swap could affect the tertiary structure assembly more profoundly than observed in the simulations. Notably, Arg596 plays a key role in positioning the aforementioned loop, which is crucial for the placement of the “arginine finger” or the Arg485 side chain during RasGTPase activation.
c.1025A>C	Y342S (3D Viewer)	Likely Pathogenic	C2	Uncertain		2				-7.996	In-Between	0.925	Likely Pathogenic	Ambiguous	0.407	Likely Benign	3.03	Destabilizing	0.1	2.87	Destabilizing	2.95	Destabilizing	0.93	Ambiguous	-6.60	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	1.75	Pathogenic	0.04	Affected	3.37	25	-3	-2	0.5	-76.10	200.1	77.8	0.0	0.0	-0.2	0.1								Potentially Pathogenic	The phenol ring of Tyr342, located at the end of an anti-parallel β sheet strand (res. Gly341-Pro349), faces outward in the C2 domain. In the WT simulations, the phenol ring of Tyr342 contributes to a triple tyrosine stack (Tyr342, Tyr328, and Tyr281) that links together three anti-parallel β sheet strands. Additionally, it shields Gly344 from the solvent, reducing its exposure and providing stability for the β-sandwich. This motif also contributes to a twist formation in the β sheet.In the variant simulations, the Ser342 side chain cannot participate in the stack formation. Instead, the hydroxyl group of the Ser342 side chain forms a hydrogen bond with the imidazole ring of His326 in a neighboring β strand (res. Ala322-Asp330). This disrupts the formation of a hydrogen bond between His326 and the carboxylate group of the Glu283 side chain from another β strand (res. Arg279-Cys285). Although these changes in surface interactions could weaken the characteristic twist that strengthens the β sheet fold, no major structural effects are observed in the variant simulations. The residue swap could also affect the SynGAP-membrane association, as the hydroxyl group of Ser342 could form hydrogen bonds with membrane-facing loop residues. However, this phenomenon cannot be addressed using solvent-only simulations.
c.743G>C	R248P (3D Viewer)	Likely Pathogenic	PH	Likely Pathogenic		1				-10.751	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.848	Likely Pathogenic	3.09	Destabilizing	0.6	8.87	Destabilizing	5.98	Destabilizing	1.21	Destabilizing	-5.97	Deleterious	0.998	Probably Damaging	0.878	Possibly Damaging	5.64	Benign	0.00	Affected	3.41	14	0	-2	2.9	-59.07	223.8	126.6	0.0	0.0	-0.2	0.1	X	X						Potentially Pathogenic	The guanidinium group of Arg248, located on an α helix (residues Ala236-Val250), forms two very stable salt bridges with Asp255 (from a short α helical section, res. Lys254-Asn256) and Glu244 (from a nearby loop) in the WT simulations. In the variant simulations, the pyrrolidine side chain of Pro248 cannot form any salt bridges, which could negatively affect the tertiary structure assembly of the PH domain. Additionally, Pro248 lacks a free amide group needed for hydrogen bonding with the backbone carbonyl group of Asn245, disrupting the continuity of the α helix.
c.1214G>C	R405P (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-14.206	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.572	Likely Pathogenic	3.11	Destabilizing	0.3	5.19	Destabilizing	4.15	Destabilizing	1.26	Destabilizing	-6.32	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.62	Benign	0.01	Affected	3.38	28	-2	0	2.9	-59.07
c.1082A>C	Q361P (3D Viewer)	Likely Pathogenic	C2	Likely Pathogenic		1				-13.280	Likely Pathogenic	0.956	Likely Pathogenic	Likely Pathogenic	0.482	Likely Benign	3.12	Destabilizing	0.0	3.45	Destabilizing	3.29	Destabilizing	0.38	Likely Benign	-3.03	Deleterious	0.996	Probably Damaging	0.979	Probably Damaging	1.63	Pathogenic	0.05	Affected	3.37	25	-1	0	1.9	-31.01
c.844T>C	C282R (3D Viewer)	Likely Pathogenic	C2	Pathogenic		2				-16.378	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.466	Likely Benign	3.13	Destabilizing	0.6	1.58	Ambiguous	2.36	Destabilizing	1.70	Destabilizing	-11.03	Deleterious	0.999	Probably Damaging	0.998	Probably Damaging	1.63	Pathogenic	0.00	Affected	3.39	18	-4	-3	-7.0	53.05	297.4	-98.2	-0.1	0.1	0.5	0.0	X		X				X	Potentially Pathogenic	The thiol-containing side chain of Cys282, located at the beginning of an anti-parallel β sheet strand (res. Arg279-Leu286), is packed against multiple hydrophobic residues (e.g., Ile268, Leu284, Trp308, Leu327). In the variant simulations, the bulky side chain of Arg282 with its positively charged guanidinium group is not suitable for this hydrophobic niche. Consequently, the hydrophobic residues must either make room to accommodate Arg282 or it must escape the hydrophobic C2 domain core.As a result, new hydrogen bonds are formed with the backbone carbonyl groups of the surrounding β sheet residues Ala399, Leu325, and His326, which decreases the unity of the secondary structure elements. Notably, it is likely that the residue swap causes major problems during the C2 domain folding that are not visible in the variant simulations. In fact, even increased lability in the C2 domain could adversely affect the establishment of a stable SynGAP-membrane association.
c.1409T>C	M470T (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-8.104	Likely Pathogenic	0.976	Likely Pathogenic	Likely Pathogenic	0.763	Likely Pathogenic	3.19	Destabilizing	0.1	2.68	Destabilizing	2.94	Destabilizing	1.49	Destabilizing	-5.30	Deleterious	0.996	Probably Damaging	0.985	Probably Damaging	-1.08	Pathogenic	0.24	Tolerated	3.37	34	-1	-1	-2.6	-30.09	213.8	46.5	0.0	0.0	-0.2	0.2		X					X	Potentially Pathogenic	The thioether group of Met470, located in the middle of an α helix (res. Ala461–Phe476), interacts with hydrophobic residues in the inter-helix space (e.g., Val473, Leu558, Cys576, Trp572) formed by two other α helices (res. Ser604–Arg581, res. Pro562–Arg579). In the WT simulations, the Met470 side chain also packs against the positively charged guanidinium groups of Arg575, Arg429, and Arg579, which form salt bridges with the negatively charged carboxylate groups of the Asp474 and Asp467 side chains at the protein surface. In the variant simulations, the hydroxyl group of the Thr470 side chain forms an H-bond with the backbone carbonyl group of Ser466 in the α helix, potentially lowering its structural integrity. Importantly, the hydroxyl group of Thr470 also forms an H-bond with the guanidinium group of Arg575, which helps it form a more permanent salt bridge with Asp467.
c.1403T>A	M468K (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-16.982	Likely Pathogenic	0.978	Likely Pathogenic	Likely Pathogenic	0.828	Likely Pathogenic	3.21	Destabilizing	0.1	3.30	Destabilizing	3.26	Destabilizing	2.57	Destabilizing	-4.61	Deleterious	0.878	Possibly Damaging	0.922	Probably Damaging	-1.34	Pathogenic	0.04	Affected	3.37	31	0	-1	-5.8	-3.02	188.7	69.3	0.0	0.0	-0.1	0.2			X				X	Potentially Pathogenic	The thioether group of Met468, located in the middle of an α helix (res. Ala461–Phe476), interacts with hydrophobic residues (e.g., Phe464, Leu465, Leu489) in an inter-helix space formed by two other α helices (res. Ala461–Phe476, res. Thr488–Gly502). In the variant simulations, the positively charged side chain of Lys468 rotates outward to escape the hydrophobic niche, forming an H-bond with the hydroxyl group of the Ser471 side chain and a salt bridge with the carboxylate group of the Glu472 side chain. This residue swap also disrupts the methionine-aromatic stacking with the phenyl ring of the Phe464 side chain. Although no large-scale structural changes are observed during the variant simulations, the importance of hydrophobic packing suggests that the effects could be more pronounced during protein folding.
c.2075T>A	L692Q (3D Viewer)	Likely Pathogenic	GAP	Pathogenic		1				-13.873	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.596	Likely Pathogenic	3.24	Destabilizing	0.1	3.27	Destabilizing	3.26	Destabilizing	2.76	Destabilizing	-5.98	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	3.06	Benign	0.00	Affected	3.42	17	-2	-2	-7.3	14.97
c.1957C>G	L653V	Likely Benign	GAP	Uncertain		1				-7.050	In-Between	0.301	Likely Benign	Likely Benign	0.146	Likely Benign	3.28	Destabilizing	0.3	2.18	Destabilizing	2.73	Destabilizing	1.32	Destabilizing	-2.25	Neutral	0.227	Benign	0.039	Benign	3.28	Benign	0.08	Tolerated			2	1	0.4	-14.03
c.2050G>C	D684H (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.194	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.613	Likely Pathogenic	3.36	Destabilizing	1.0	2.95	Destabilizing	3.16	Destabilizing	0.55	Ambiguous	-6.98	Deleterious	1.000	Probably Damaging	0.972	Probably Damaging	3.36	Benign	0.00	Affected	3.42	17	-1	1	0.3	22.05
c.968T>C	L323P (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-12.507	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.762	Likely Pathogenic	3.39	Destabilizing	0.6	8.46	Destabilizing	5.93	Destabilizing	2.20	Destabilizing	-4.80	Deleterious	0.999	Probably Damaging	0.977	Probably Damaging	0.59	Pathogenic	0.01	Affected	4.29	398	-3	-3	-5.4	-16.04	201.9	68.2	0.0	0.1	0.6	0.3	X							Potentially Pathogenic	The iso-butyl side chain of Leu323, located at the beginning of an anti-parallel β sheet strand (res. Ala322-Asp330), packs against multiple hydrophobic leucine residues (e.g., Leu264, Leu266, Leu284, Leu286). In contrast, in the variant simulations, the less bulky cyclic five-membered pyrrolidine ring of Pro323 cannot fill the hydrophobic space as effectively as the branched hydrocarbon side chain of leucine. Notably, the backbone amide group of Leu323 forms a hydrogen bond with the backbone carbonyl group of Cys285. Pro323 cannot form this bond due to the absence of the backbone amide group, resulting in partial unfolding of the anti-parallel β sheet end in the variant simulations.
c.1813C>T	P605S (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-10.830	Likely Pathogenic	0.987	Likely Pathogenic	Likely Pathogenic	0.718	Likely Pathogenic	3.40	Destabilizing	0.1	3.34	Destabilizing	3.37	Destabilizing	1.00	Destabilizing	-7.96	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	0.70	Pathogenic	0.00	Affected	3.37	35	1	-1	0.8	-10.04	213.8	-15.4	-0.3	0.2	0.2	0.1				X			X	Potentially Pathogenic	Pro605 is located in a short turn between an α helix (res. Glu582-Met603) and a short α helical section (res. Ser606-Phe608). The pyrrolidine side chain of Pro605 packs hydrophobically with nearby hydrophobic residues (e.g., Ile514, Leu623, Leu610) in the inter-helix space. Additionally, proline lacks a free backbone amide group, which breaks the α helix and facilitates the turn in the WT structure.In the variant simulations, the hydroxyl side chain of Ser605 forms hydrogen bonds with the backbone carbonyl groups of Ala601 and Ile602. Importantly, the helix end is more stable than with Pro605 in the WT. Indeed, proline is a more effective secondary structure breaker compared to serine.Thus, the residue swap could have a more profound effect on the actual folding process, for example, by preventing the bending at the α helix end, than what the simulations suggest. Moreover, due to its location at the GAP-Ras interface, the residue swap could affect the GAP-Ras association.
c.791T>A	L264Q (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-15.729	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.678	Likely Pathogenic	3.43	Destabilizing	0.1	2.41	Destabilizing	2.92	Destabilizing	2.48	Destabilizing	-5.52	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	0.49	Pathogenic	0.00	Affected	3.38	18	-2	-2	-7.3	14.97	254.7	-7.6	0.0	0.0	0.0	0.3	X		X				X	Potentially Pathogenic	The iso-butyl branched hydrocarbon side chain of Leu264, located at the end of an anti-parallel β sheet strand (res. Arg259-Arg272), packs against multiple hydrophobic residues such as Leu266, Phe314, Leu317, and Leu323 in the WT simulations. In the variant simulations, the hydrophilic carboxamide group of the Gln264 side chain is not suitable for the hydrophobic niche, causing the hydrophobic residues to make room for the swapped residue. Additionally, the carboxamide group of Gln264 forms hydrogen bonds with the backbone amide groups of Arg405 and Lys256 in the β sheet and the carbonyl group of Val350 in an α helical section of a nearby loop (res. Pro359-Phe358). The residue swap disrupts the packing of the C2 domain, which could adversely affect the C2 domain structure during folding. This disruption could potentially weaken the stability of the SynGAP-membrane association.
c.1403T>C	M468T (3D Viewer)	Likely Pathogenic	GAP	Uncertain		2	6-33438435-T-C	1	6.20e-7	-12.399	Likely Pathogenic	0.862	Likely Pathogenic	Ambiguous	0.801	Likely Pathogenic	3.47	Destabilizing	0.1	3.10	Destabilizing	3.29	Destabilizing	1.84	Destabilizing	-3.85	Deleterious	0.994	Probably Damaging	0.985	Probably Damaging	-1.31	Pathogenic	0.01	Affected	3.37	31	-1	-1	-2.6	-30.09	214.6	47.1	0.0	0.0	0.1	0.0							X	Potentially Pathogenic	The thioether group of Met468, located in the middle of an α helix (res. Ala461–Phe476), interacts with hydrophobic residues (e.g., Phe464, Leu465, Leu489) in an inter-helix space formed by two other α helices (res. Ala461–Phe476, res. Thr488–Gly502). In the variant simulations, the hydrophilic side chain of Thr468 does not pack favorably in the hydrophobic niche, and the methionine-aromatic stacking is lost. Although the hydroxyl group of Thr468 forms an H-bond with the backbone carbonyl group of Phe464, the integrity of the α helix is not affected in the simulations. No large-scale structural changes are observed during the variant simulations; however, due to the importance of hydrophobic packing, the effects could be more pronounced during protein folding.
c.2131C>G	L711V (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1	6-33441596-C-G	1	6.20e-7	-10.045	Likely Pathogenic	0.709	Likely Pathogenic	Likely Benign	0.170	Likely Benign	3.48	Destabilizing	0.1	2.22	Destabilizing	2.85	Destabilizing	1.40	Destabilizing	-2.59	Deleterious	0.992	Probably Damaging	0.970	Probably Damaging	3.34	Benign	0.00	Affected	3.50	9	1	2	0.4	-14.03
c.1685C>T	P562L (3D Viewer)	Likely Pathogenic	GAP	Pathogenic/Likely path.		10	6-33440737-C-T			-13.438	Likely Pathogenic	0.996	Likely Pathogenic	Likely Pathogenic	0.829	Likely Pathogenic	3.54	Destabilizing	0.8	0.17	Likely Benign	1.86	Ambiguous	-0.14	Likely Benign	-9.95	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	0.58	Pathogenic	0.00	Affected	3.37	35	-3	-3	5.4	16.04	228.8	-68.5	-0.1	0.0	0.1	0.2							X	Potentially Pathogenic	Pro562 is located on an α-α loop between two α-helices (res. Ala533-Val560 and res. Arg563-Glu578). The cyclic pyrrolidine side chain of Pro562 hydrophobically packs with other residues in the inter-helix space, such as Leu565, Ile501, and Phe561. In the variant simulations, Leu562 packs more favorably with the nearby hydrophobic residues, and the backbone amide group of Leu562 (absent in proline) does not form any intra-protein hydrogen bonds. However, prolines are well-suited for unstructured regions like loops, and thus, Pro562 in the WT is necessary at the end of the helix to induce a tight turn during folding. Although no negative structural effects are observed during the simulations, the residue swap could potentially cause extensive damage to the protein structure during folding.	10.1016/j.ajhg.2020.11.011
c.2143C>T	P715S (3D Viewer)		GAP	Likely Pathogenic		1	6-33441608-C-T	1	6.20e-7	-7.635	In-Between	0.787	Likely Pathogenic	Ambiguous	0.277	Likely Benign	3.54	Destabilizing	0.0	0.81	Ambiguous	2.18	Destabilizing	0.94	Ambiguous	-7.17	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	3.43	Benign	0.01	Affected	3.50	9	1	-1	0.8	-10.04	231.8	-14.0	-0.1	0.0	-0.8	0.1							X	Uncertain	Pro715, along with Gly712 and Pro713, are located in a hinge region of an α-helix making a ~90-degree turn (res. Lys705-Leu725). In the WT simulations, the pyrrolidine side chain of Pro715, lacking the backbone amide groups altogether, forces the tight helix turn to take place while also hydrophobically packing with nearby residues (e.g., Leu700, Leu708, Leu714, and Leu718). Leu715, with a normal amide backbone, could potentially affect protein folding and turn formation, although this was not observed in the variant simulations. Additionally, the hydroxyl group of the Ser715 side chain can form hydrogen bonds with the backbone carbonyl group of Gly712 and disrupt the hydrophobic packing arrangement of the leucine residues from the neighboring α-helices, impacting the GAP domain tertiary assembly.
c.1390T>G	F464V (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-12.254	Likely Pathogenic	0.994	Likely Pathogenic	Likely Pathogenic	0.592	Likely Pathogenic	3.61	Destabilizing	0.1	2.89	Destabilizing	3.25	Destabilizing	1.40	Destabilizing	-6.96	Deleterious	0.998	Probably Damaging	0.996	Probably Damaging	3.36	Benign	0.04	Affected	3.37	34	-1	-1	1.4	-48.04	210.1	40.5	-0.1	0.0	-0.9	0.3							X	Potentially Pathogenic	The phenyl ring of Phe464, located in the middle of an α helix (res. Ala461–Phe476), packs against hydrophobic residues (e.g., Met468, Leu451, Leu455, and Tyr428) in the inter-helix space formed with two other α helices (res. Asn440-Lys460 and res. Pro413-Glu436). The iso-propyl side chain of Val464 is similarly hydrophobic but considerably smaller than the original phenyl ring of Phe464. To compensate for the size difference, neighboring residues need to fill in the gap in the variant simulations.The phenolic side chain of Tyr428, located at the middle bend of an α helix (res. Glu436-Pro413), assumes a new position in the inter-helix space or rotates inward next to the third α helix (res. Asn440-Lys460) when the stable H-bond between Tyr428 and Asp467 seen in the WT simulations breaks. The residue swap also leads to the loss of the methionine-aromatic interaction between the Met468 and Phe464 side chains, which could weaken the integrity of the parent α helix (res. Ala461-Phe476). Although the simulations likely underestimate the full adverse effect of the introduced mutation during folding, the two opposing α helices (res. Ala461–Phe476 and res. Glu436-Pro413) move substantially closer to each other in the variant simulations.
c.878G>C	R293P (3D Viewer)	Likely Pathogenic	C2	Likely Pathogenic		1				-16.275	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.497	Likely Benign	3.62	Destabilizing	0.4	9.06	Destabilizing	6.34	Destabilizing	0.47	Likely Benign	-6.43	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	1.45	Pathogenic	0.01	Affected	3.38	23	0	-2	2.9	-59.07	202.3	132.0	0.1	0.0	0.1	0.1	X	X		X				Potentially Pathogenic	The guanidinium group of the Arg293 side chain, located in an anti-parallel β sheet strand (res. Met289-Pro298), packs against the phenol ring of the Tyr281 side chain or forms a salt bridge with the carboxylate group of Glu283 on the outer side of the C2 domain. In the WT simulations, the positively charged side chain of arginine remains outside the hydrophobic C2 domain, resulting in a twist in the β strand. The backbone amide bond of Arg293 potentially maintains this twist by forming a hydrogen bond with the carbonyl group of His210 or the hydroxyl group of Ser211 in the anti-parallel β sheet.Although this twist is also maintained in the variant simulations, replacing the positively charged residue with proline, which lacks the backbone amide group altogether, causes the β strand to unfold. Because Arg293 is positioned at the C2 and PH domain interface, the residue swap could significantly impact the tertiary structure assembly. Notably, Arg293 is located at the SynGAP-Ras interface, and its role in complex formation cannot be fully understood through solvent-only simulations.
c.1367A>C	Q456P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-15.250	Likely Pathogenic	0.993	Likely Pathogenic	Likely Pathogenic	0.469	Likely Benign	3.68	Destabilizing	0.2	8.43	Destabilizing	6.06	Destabilizing	0.82	Ambiguous	-5.66	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	3.34	Benign	0.07	Tolerated	3.37	34	-1	0	1.9	-31.01
c.1157G>A	G386E (3D Viewer)		C2	Uncertain		1	6-33438062-G-A			-9.286	Likely Pathogenic	0.686	Likely Pathogenic	Likely Benign	0.447	Likely Benign	3.69	Destabilizing	2.9	0.79	Ambiguous	2.24	Destabilizing	0.54	Ambiguous	-0.83	Neutral	0.860	Possibly Damaging	0.354	Benign	3.93	Benign	0.01	Affected	4.32	3	-2	0	-3.1	72.06
c.1199T>A	V400E (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-13.686	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.810	Likely Pathogenic	3.70	Destabilizing	0.2	2.46	Destabilizing	3.08	Destabilizing	2.29	Destabilizing	-4.88	Deleterious	0.920	Possibly Damaging	0.335	Benign	5.31	Benign	0.00	Affected	3.38	27	-2	-2	-7.7	29.98	249.1	-38.8	-0.1	0.1	1.0	0.0	X		X				X	Potentially Pathogenic	The iso-propyl side chain of Val400, located in an anti-parallel β sheet strand (res. Ala399-Ile411), hydrophobically packs against hydrophobic residues within the anti-parallel β sheet of the C2 domain (e.g., Ile268, Ala404, Leu325, Leu402). In the variant simulations, the negatively charged carboxylate group of the Glu400 side chain is not suitable for occupying the hydrophobic niche. Consequently, the side chain escapes the center of the C2 domain and interacts with the backbone amide groups of Leu402 in the same β strand and/or Ile269 and Glu270 in a neighboring β strand (res. Arg259-Arg272). This residue swap disrupts the hydrophobic packing and generally has extensive negative effects on the C2 domain structure. At a minimum, the residue swap could affect the C2 domain stability and membrane association.
c.1558T>C	S520P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-12.707	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.855	Likely Pathogenic	3.72	Destabilizing	0.8	8.86	Destabilizing	6.29	Destabilizing	0.83	Ambiguous	-4.57	Deleterious	0.997	Probably Damaging	0.986	Probably Damaging	-1.32	Pathogenic	0.01	Affected			1	-1	-0.8	10.04
c.1991T>C	L664S (3D Viewer)	Likely Pathogenic	GAP	Likely Benign		1	6-33441250-T-C	1	6.20e-7	-16.498	Likely Pathogenic	0.997	Likely Pathogenic	Likely Pathogenic	0.543	Likely Pathogenic	3.75	Destabilizing	0.2	3.63	Destabilizing	3.69	Destabilizing	2.77	Destabilizing	-5.99	Deleterious	1.000	Probably Damaging	0.996	Probably Damaging	2.85	Benign	0.00	Affected	3.38	28	-3	-2	-4.6	-26.08	215.5	50.1	0.0	0.0	-0.2	0.2						X		Potentially Benign	The iso-butyl side chain of L664, located on an α-helix (res. Ser641-Glu666), hydrophobically interacts with residues in the inter-helix space between three helices (res. Glu617-Asn635, res. Glu582-Met603, and res. Ser641-Glu666), such as Ile589, Phe663, and Met660. In the variant simulations, the hydroxyl group of Ser664 forms hydrogen bonds with the backbone carbonyl oxygen of another helix residue, such as Met660 or Gln661. This interaction is known to destabilize hydrogen bonding in the α-helix, but this effect was not observed in the simulations. Additionally, Ser664 occasionally forms hydrogen bonds with the carboxylate group of Asp586 on another α-helix (res. Glu582-Met603), which could minimally influence the tertiary structure assembly. Despite these interactions, no major negative effects on the protein structure were observed during the simulations.
c.968T>G	L323R (3D Viewer)	Likely Pathogenic	C2	Likely Pathogenic		1				-14.568	Likely Pathogenic	0.997	Likely Pathogenic	Likely Pathogenic	0.692	Likely Pathogenic	3.75	Destabilizing	0.4	4.47	Destabilizing	4.11	Destabilizing	2.15	Destabilizing	-4.70	Deleterious	0.999	Probably Damaging	0.969	Probably Damaging	0.59	Pathogenic	0.01	Affected	3.39	22	-3	-2	-8.3	43.03	261.8	-61.6	-0.4	0.2	0.8	0.2	X		X				X	Potentially Pathogenic	The iso-butyl side chain of Leu323, located at the beginning of an anti-parallel β sheet strand (res. Ala322-Asp330), packs against multiple hydrophobic leucine residues (e.g., Leu264, Leu266, Leu284, Leu286). In contrast, in the variant simulations, the positively charged guanidinium group of the Arg323 side chain is unsuitable for the hydrophobic niche. Consequently, the side chain either rotates away from the center of the C2 domain or, if it remains within the C2 domain core, it reorients nearby residues to form hydrogen bonds. Regardless, the residue swap extensively disrupts the C2 domain structure.
c.1771G>C	A591P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.479	Likely Pathogenic	0.991	Likely Pathogenic	Likely Pathogenic	0.404	Likely Benign	3.78	Destabilizing	0.3	7.29	Destabilizing	5.54	Destabilizing	1.45	Destabilizing	-4.41	Deleterious	0.995	Probably Damaging	0.853	Possibly Damaging	3.35	Benign	0.01	Affected	3.37	35	1	-1	-3.4	26.04	191.5	-10.1	0.2	0.1	0.4	0.1	X							Potentially Pathogenic	The methyl group of the Ala591 side chain, located in the middle of an α helix (res. Glu582-Met603), packs against hydrophobic residues (e.g., Ile483, Phe484) of an opposing partially helical loop (res. Phe476-Asn487).In the variant simulations, Pro591 lacks a free backbone amide group and, therefore, cannot form a hydrogen bond with the backbone carbonyl of Arg587 as Ala591 does in the WT. This notably weakens the α helix integrity and compromises the continuity of the helix. In reality, the effect on the structure during protein folding could be more severe.
c.1505G>A	G502D (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.796	Likely Pathogenic	0.994	Likely Pathogenic	Likely Pathogenic	0.915	Likely Pathogenic	3.79	Destabilizing	0.9	5.69	Destabilizing	4.74	Destabilizing	1.38	Destabilizing	-6.80	Deleterious	0.999	Probably Damaging	0.977	Probably Damaging	-1.66	Pathogenic	0.00	Affected	3.37	35	1	-1	-3.1	58.04	224.2	-80.0	-0.8	0.7	0.6	0.3	X		X				X	Potentially Pathogenic	Gly502 is located in a hinge in the middle of an α-helix (res. Leu489-Glu519). In the WT, Gly502 acts as an α-helix breaker due to its lack of a side chain, facilitating a bend in the middle of the α-helix. In the variant simulations, the carboxylate group of Asp502 forms hydrogen bonds with neighboring residues (e.g., Ser677, Lys504), disrupting the hinge. Additionally, Asp502 struggles to fit into the α-helix hinge and cannot generate a similar bend as Gly502, which would drastically affect the secondary structure during folding. Thus, the deleterious effect seen in the simulations is likely an underestimate of the impact of the residue swap on the protein structure during protein folding.
c.1493T>G	M498R (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-8.812	Likely Pathogenic	0.988	Likely Pathogenic	Likely Pathogenic	0.869	Likely Pathogenic	3.85	Destabilizing	0.2	2.35	Destabilizing	3.10	Destabilizing	1.76	Destabilizing	-4.53	Deleterious	0.464	Possibly Damaging	0.120	Benign	-1.36	Pathogenic	0.00	Affected			0	-1	-6.4	24.99
c.1349C>A	A450E (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-16.578	Likely Pathogenic	0.989	Likely Pathogenic	Likely Pathogenic	0.653	Likely Pathogenic	3.86	Destabilizing	0.2	5.23	Destabilizing	4.55	Destabilizing	1.59	Destabilizing	-4.67	Deleterious	0.999	Probably Damaging	0.992	Probably Damaging	3.38	Benign	0.07	Tolerated	3.37	32	0	-1	-5.3	58.04	240.1	-82.6	0.0	0.0	0.7	0.0			X				X	Potentially Pathogenic	The methyl group of Ala450, located in an α helix (res. Asn440-Thr458), packs against hydrophobic residues in the inter-helix space (e.g., Leu692). In the variant simulations, the carboxylate group of the Glu450 side chain rotates outward, away from the hydrophobic niche, where it does not form any lasting salt bridges or H-bonds. Although the residue swap does not negatively affect the protein structure based on the simulations, it is possible that the introduction of the negatively charged residue adversely affects the folding process or tertiary assembly.
c.1490A>G	Y497C (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-11.872	Likely Pathogenic	0.948	Likely Pathogenic	Ambiguous	0.806	Likely Pathogenic	3.88	Destabilizing	0.1	4.76	Destabilizing	4.32	Destabilizing	1.40	Destabilizing	-8.82	Deleterious	1.000	Probably Damaging	0.995	Probably Damaging	-1.65	Pathogenic	0.03	Affected	3.37	35	0	-2	3.8	-60.04	209.9	59.1	-0.1	0.0	-0.3	0.1		X					X	Potentially Pathogenic	Tyr497 is located in the α-helix (res. Leu489-Glu519) within the inter-helix space of four α-helices (res. Leu489-Ile501, res. Val441-Ser457, res. Arg563-Glu578, res. Ala461-Val473). In the WT simulations, the phenol ring of Tyr497 hydrophobically packs with other residues in the inter-helix space (e.g., Leu465, Leu565, Val568). The hydroxyl group of Tyr497 also alternately forms hydrogen bonds with the carboxylate side chain of Gln456 and the backbone carbonyl of Glu564. Thus, Tyr497 plays a role in the folding and maintenance of the tertiary structure assembly between these four helices.In the variant simulations, the comparatively smaller residue, Cys497, cannot maintain any of the interactions seen with Tyr497 in the WT. Although no severe deleterious consequences are observed in the simulations, the structural effects could be more pronounced during actual protein folding. Indeed, the tertiary structure is seen to slightly break apart in the variant simulations.
c.2162T>G	I721S (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.032	Likely Pathogenic	0.996	Likely Pathogenic	Likely Pathogenic	0.466	Likely Benign	3.91	Destabilizing	0.1	3.96	Destabilizing	3.94	Destabilizing	2.28	Destabilizing	-5.26	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.21	Pathogenic	0.00	Affected	3.50	9	-1	-2	-5.3	-26.08	203.3	49.3	-0.1	0.0	-1.1	0.0							X	Uncertain	The sec-butyl side chain of Ile721, located on an α-helix (res. Leu714-Arg726), engages in hydrophobic packing with other residues in the hydrophobic inter-helix space, such as Phe420, Tyr417, His693, and Leu717. In the variant simulations, the hydroxyl side chain of Ser721 forms hydrogen bonds with nearby residues, such as Leu717 and His693. Although no major structural changes are observed during the variant simulations, the hydrophilic residue Ser721 could disrupt the hydrophobic packing during folding. However, because the model ends abruptly at the C-terminus, no definite conclusions can be drawn based on the simulations.
c.896G>A	R299H (3D Viewer)		C2	Conflicting		2	6-33437801-G-A	10	6.20e-6	-7.731	In-Between	0.388	Ambiguous	Likely Benign	0.238	Likely Benign	3.97	Destabilizing	1.0	0.94	Ambiguous	2.46	Destabilizing	1.41	Destabilizing	-3.35	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	1.69	Pathogenic	0.02	Affected	3.39	19	2	0	1.3	-19.05	211.2	72.5	-0.1	0.2	-0.2	0.3	X							Potentially Pathogenic	The guanidinium group of Arg299, located in a β hairpin loop linking two anti-parallel β sheet strands (res. Met289-Pro298, res. Thr305-Asn315), forms hydrogen bonds that stabilize the tight turn. In the WT simulations, the Arg299 side chain hydrogen bonds with the loop backbone carbonyl groups (e.g., Ser302, Thr305, Leu274, Gly303), the hydroxyl group of Ser300, and even forms a salt bridge with the carboxylate group of Asp304.In the variant simulations, the imidazole ring of His299 (epsilon protonated state) hydrogen bonds with the carbonyl group of Asp304 and the hydroxyl group of Ser300. However, it does not form as many or as strong interactions as arginine, which could affect the initial formation of the secondary hairpin loop during folding. β hairpins are potential nucleation sites during the initial stages of protein folding, so even minor changes in them could be significant.Additionally, His299 prefers to hydrophobically interact with other hydrophobic residues inside the C2 domain core (e.g., Val306, Leu274), which destabilizes the C2 domain. Indeed, the β strand partially unfolds during the second simulation. Moreover, the positively charged Arg299 side chain faces the polar head group region of the inner leaflet membrane and could directly anchor the C2 domain to the membrane. In short, the residue swap could negatively affect both protein folding and the stability of the SynGAP-membrane association.
c.1529T>G	I510S (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-11.661	Likely Pathogenic	0.955	Likely Pathogenic	Ambiguous	0.926	Likely Pathogenic	4.00	Destabilizing	0.1	3.78	Destabilizing	3.89	Destabilizing	2.34	Destabilizing	-4.63	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	-1.44	Pathogenic	0.00	Affected	3.37	35	-1	-2	-5.3	-26.08	201.4	45.9	-0.4	0.2	0.0	0.3							X	Potentially Pathogenic	Ile510 is located in the middle of an α-helix (res. Gly502-Tyr518) within the inter-helix space of three helices (res. Gly502-Tyr518, Ala533-Val560, and res. Glu582-Met603). In the WT simulations, the sec-butyl side chain of Ile510 hydrophobically packs with other residues in the inter-helix space (e.g., Leu506, Leu610, Ile514, Ile602, Leu598). In the variant simulations, the hydroxyl group of Ser510 forms a hydrogen bond with the backbone atoms of Leu506 and Gly511 in the same α-helix, which could further weaken the α-helix integrity. This α-helix already shows weakness in the WT simulations due to Gly511. Although the simulations do not show large-scale effects, the residue swap could have a substantial impact due to the fundamental role of hydrophobic packing during protein folding.
c.703T>C	S235P (3D Viewer)	Likely Pathogenic	PH	Likely Pathogenic		1				-14.857	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.870	Likely Pathogenic	4.02	Destabilizing	0.1	6.91	Destabilizing	5.47	Destabilizing	1.23	Destabilizing	-4.24	Deleterious	0.917	Possibly Damaging	0.446	Benign	5.47	Benign	0.01	Affected	3.40	14	1	-1	-0.8	10.04	201.5	17.0	0.1	0.0	-0.6	0.0		X						Potentially Pathogenic	In the WT, the hydroxyl group of Ser235, located in a β-α loop between an anti-parallel β sheet strand (res. Gly227-Phe231) and an α helix (residues Ala236-Val250), forms hydrogen bonds with the GAP domain loop residue Glu680 and with the backbone amide groups of Ala237 and Glu238 from the α helix. In the variant simulations, the pyrrolidine ring of Pro235 cannot stabilize the α helix end or maintain tertiary bonding interactions between the PH and GAP domains via hydrogen bonding as effectively as serine.
c.1205T>G	L402R (3D Viewer)	Likely Pathogenic	C2	Likely Pathogenic		1				-13.800	Likely Pathogenic	0.997	Likely Pathogenic	Likely Pathogenic	0.522	Likely Pathogenic	4.10	Destabilizing	0.2	3.82	Destabilizing	3.96	Destabilizing	2.24	Destabilizing	-4.69	Deleterious	0.967	Probably Damaging	0.459	Possibly Damaging	3.69	Benign	0.00	Affected	3.38	28	-3	-2	-8.3	43.03	259.5	-55.4	0.0	0.0	1.4	0.0	X		X				X	Potentially Pathogenic	The iso-butyl side chain of Leu402, located in an anti-parallel β sheet strand (res. Ala399-Ile411), packs with residues inside the hydrophobic core of the C2 domain (e.g., Ile268, Ala404, Leu266, Val400). In the variant simulations, the positively charged guanidinium group of the Arg402 side chain is not suitable for the hydrophobic niche. Consequently, the side chain moves outward from the hydrophobic C2 domain core and stacks with the phenol ring of Tyr363 or forms H-bonds with the carboxamide group of the Gln361 side chain in the β sheet strand (res. Thr359-Tyr364). This movement induces extensive negative effects on the C2 domain structure.
c.1118G>A	G373E (3D Viewer)		C2	Uncertain		1				-7.281	In-Between	0.569	Likely Pathogenic	Likely Benign	0.420	Likely Benign	4.13	Destabilizing	3.2	0.52	Ambiguous	2.33	Destabilizing	-0.02	Likely Benign	-0.69	Neutral	0.001	Benign	0.000	Benign	3.90	Benign	0.01	Affected			0	-2	-3.1	72.06
c.1763T>A	L588H (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-16.947	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.939	Likely Pathogenic	4.20	Destabilizing	0.2	3.69	Destabilizing	3.95	Destabilizing	2.26	Destabilizing	-6.97	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.42	Pathogenic	0.00	Affected	3.38	34	-2	-3	-7.0	23.98	214.3	20.9	0.0	0.0	0.0	0.2	X	X					X	Potentially Pathogenic	The isobutyl group of the Leu588 side chain, located in an α helix (res. Glu582-Met603), packs against hydrophobic residues in the inter-helix hydrophobic space (e.g., Ile584, Trp572, Phe484, Met470, Val473, Ile483).In the variant simulations, the imidazole ring of His588 is aromatic but contains polar delta and epsilon nitrogen atoms that are not suited for the hydrophobic niche. The protonated epsilon nitrogen forms a hydrogen bond with the backbone carbonyl group of Ala469, which can disrupt the continuity of the opposing α helix (res. Phe476-Lys460).While the residue swap could affect the tertiary assembly and the underlying protein folding process, it is difficult to determine if the mutation would be tolerated based solely on the variant simulations.
c.1172G>T	G391V (3D Viewer)	Likely Benign	C2	Likely Benign		1	6-33438077-G-T	3	1.86e-6	-6.642	Likely Benign	0.133	Likely Benign	Likely Benign	0.595	Likely Pathogenic	4.23	Destabilizing	1.3	4.81	Destabilizing	4.52	Destabilizing	-0.11	Likely Benign	-0.98	Neutral	0.994	Probably Damaging	0.887	Possibly Damaging	1.32	Pathogenic	0.10	Tolerated	3.69	8	-1	-3	4.6	42.08	228.6	-69.0	0.0	0.8	-0.5	0.3								Uncertain	Gly387 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364 and res. Ala399-Ile411). The Ω loop is assumed to directly interact with the membrane, and it is observed to move arbitrarily throughout the WT solvent simulations. This loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone.Ω loops are known to play significant roles in protein functions that require flexibility, and thus hydrophobic residues like valine are rarely tolerated. Although no negative structural effects are visualized in the variant’s simulations, Val391 may exert drastic effects on the SynGAP-membrane complex dynamics and stability. Since the effects on the Gly-rich Ω loop dynamics can only be well studied through the SynGAP-membrane complex, no definite conclusions can be drawn.
c.1136C>G	S379W (3D Viewer)		C2	Uncertain		1	6-33438041-C-G			-8.898	Likely Pathogenic	0.388	Ambiguous	Likely Benign	0.520	Likely Pathogenic	4.32	Destabilizing	3.4	3.56	Destabilizing	3.94	Destabilizing	0.16	Likely Benign	-1.02	Neutral	0.998	Probably Damaging	0.844	Possibly Damaging	3.82	Benign	0.01	Affected	4.32	11	-2	-3	-0.1	99.14	271.3	-75.7	1.4	1.0	0.6	0.5								Uncertain	Ser379 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364, res. Ala399-Ile411). Because the Ω loop is assumed to directly interact with the membrane, it moves arbitrarily throughout the WT solvent simulations. The Ω loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone.Ω loops are known to play major roles in protein functions that require flexibility, and thus hydrophobic residues like tryptophan are rarely tolerated. Although no major negative structural effects are observed in the variant simulations, Trp379 may exert drastic effects on the SynGAP-membrane complex dynamics and stability. However, since the effect on Gly-rich Ω loop dynamics can only be studied through the SynGAP-membrane complex, no definite conclusions can be drawn
c.917T>A	V306D (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-18.289	Likely Pathogenic	0.986	Likely Pathogenic	Likely Pathogenic	0.530	Likely Pathogenic	4.40	Destabilizing	0.3	4.29	Destabilizing	4.35	Destabilizing	2.44	Destabilizing	-5.44	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	1.74	Pathogenic	0.00	Affected	3.38	19	-2	-3	-7.7	15.96	212.3	-18.3	-0.2	0.4	0.0	0.2	X		X				X	Potentially Pathogenic	The isopropyl group of Val396, located at the beginning of an anti-parallel β sheet strand (res. Thr305-Asn315), packs against multiple hydrophobic residues (e.g., Leu274, Trp308, Ala271) in the WT simulations. However, in the variant simulations, the negatively charged carboxylate group of the Asp306 side chain is not suitable for this hydrophobic niche. Consequently, the side chain moves out to interact with Ser300 in the β strand (res. Met289-Arg299) and the guanidinium group of Arg299 in the β hairpin loop.In the third simulation, the residue swap disrupts the C2 domain secondary structure and tertiary assembly to a large degree when the amino group of the Lys297 side chain rotates to form a salt bridge with Asp306. This drastic effect could potentially reflect the challenge presented by the residue swap during the C2 domain folding. Because the residue swap affects the C2 domain structure, the SynGAP-membrane association could also be impacted. However, this is beyond the scope of the solvent-only simulations to unravel.
c.878G>A	R293H	Likely Pathogenic	C2	Uncertain		1				-13.009	Likely Pathogenic	0.973	Likely Pathogenic	Likely Pathogenic	0.438	Likely Benign	4.45	Destabilizing	2.3	2.12	Destabilizing	3.29	Destabilizing	0.32	Likely Benign	-4.60	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	1.45	Pathogenic	0.04	Affected			2	0	1.3	-19.05
c.1058T>C	L353P (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-7.913	In-Between	0.936	Likely Pathogenic	Ambiguous	0.464	Likely Benign	4.63	Destabilizing	0.1	10.19	Destabilizing	7.41	Destabilizing	2.17	Destabilizing	-3.70	Deleterious	0.947	Possibly Damaging	0.454	Possibly Damaging	1.29	Pathogenic	0.02	Affected	3.37	25	-3	-3	-5.4	-16.04
c.1631G>C	R544P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		2				-16.905	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.762	Likely Pathogenic	4.70	Destabilizing	0.1	4.19	Destabilizing	4.45	Destabilizing	1.14	Destabilizing	-4.88	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.48	Pathogenic	0.05	Affected	3.37	35	0	-2	2.9	-59.07	192.0	123.8	0.1	0.0	-0.3	0.0	X	X						Potentially Pathogenic	Arg544 is located in the middle of an α-helix (res. Ala533-Val560). In the WT simulations, the guanidinium side chain of Arg544 forms a salt bridge with the carboxylate groups of Glu548 on the same α-helix, and with Glu651 and Glu656 on an opposing α-helix (res. Glu666-Asp644). In the variant simulations, the pyrrolidine side chain of Pro544 cannot form any of the salt bridges that Arg544 does in the WT, potentially weakening the tertiary structure assembly. Additionally, Pro544 lacks the amide group, and thus, unlike Arg544 in the WT, is unable to form a hydrogen bond with the carbonyl of Gln540. This disruption breaks the continuity of the secondary structure element, causing the α-helix to bend slightly in the variant simulations. These negative structural effects could be more pronounced during protein folding and are likely to be undermined in the MD simulations.
c.812C>A	A271D (3D Viewer)	Likely Pathogenic	C2	Pathogenic		1				-18.590	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.706	Likely Pathogenic	4.71	Destabilizing	0.4	2.67	Destabilizing	3.69	Destabilizing	1.59	Destabilizing	-5.52	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	0.62	Pathogenic	0.00	Affected	3.38	19	0	-2	-5.3	44.01	226.2	-63.4	0.0	0.0	0.9	0.1	X		X	X			X	Potentially Pathogenic	The methyl group of Ala271, located near the end of an anti-parallel β sheet strand (res. Arg259-Arg272), packs against multiple hydrophobic residues such as Val400, Val306, and Leu274 in the WT simulations. In the variant simulations, the carboxylate group of Asp271 is not suitable for the hydrophobic niche, causing the hydrophobic residues to make room for the swapped residue. Additionally, the carboxylate group of the Asp271 side chain forms hydrogen bonds with the backbone amide groups of Arg272 and Ala399 in the β sheet, or even forms a salt bridge with the amino group of the Lys394 side chain. This directly affects the integrity of the anti-parallel β sheet at the end. In short, the residue swap disrupts the C2 domain packing during folding, which could weaken the stability of the SynGAP-membrane association.
c.1714T>C	W572R (3D Viewer)	Likely Pathogenic	GAP	Not provided		1				-17.511	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.894	Likely Pathogenic	4.84	Destabilizing	0.1	6.19	Destabilizing	5.52	Destabilizing	1.79	Destabilizing	-12.81	Deleterious					-1.25	Pathogenic	0.00	Affected	3.37	35	2	-3	-3.6	-30.03	312.6	-37.6	0.0	0.0	-1.0	0.0		X	X					Potentially Pathogenic	The indole ring of Trp572, located in an α-helix (res. Arg563-Glu578), lies in a hydrophobic inter-helix space, where it makes extensive hydrophobic interactions with nearby residues such as Met470, Phe569, Leu588, and Ile589. The guanidinium group of Arg572 is similarly sized to the tryptophan it replaced; however, it is also positively charged. In the variant simulations, Arg572 forms hydrogen bonds with other residues in the inter-helix space, such as Ser592 and the backbone carbonyl atom of Leu465. Additionally, Arg572 hydrophobically packs its carbon chain with surrounding residues such as Phe569 and Ile589.However, the introduced residue arginine is too hydrophilic and charged for the hydrophobic space, disrupting the hydrophobic packing of the inter-helix space. Indeed, in the second simulation, Arg572 successfully escapes the hydrophobic niche completely, causing the whole protein to partially unfold.Overall, the residue swap is highly likely to cause critical protein folding problems, as evidenced by the effects seen in the variant simulations.
c.2068T>C	S690P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.568	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.431	Likely Benign	4.84	Destabilizing	0.3	4.40	Destabilizing	4.62	Destabilizing	1.42	Destabilizing	-4.77	Deleterious	0.998	Probably Damaging	0.790	Possibly Damaging	3.44	Benign	0.01	Affected	3.42	17	1	-1	-0.8	10.04	207.5	15.1	0.1	0.0	-0.1	0.2	X	X						Potentially Pathogenic	The hydroxyl side chain of Ser690, located in an α-helix (res. Leu696-Leu685), forms a hydrogen bond with the backbone carbonyl group of Ser410 in an anti-parallel β-sheet of the C2 domain (res. Ile411-Ala399). In the variant simulations, the pyrrolidine side chain of Pro690 cannot form hydrogen bonds with the C2 domain residue, resulting in the loss of this inter-domain connection. Additionally, prolines lack a free amide group necessary for hydrogen bonding with the carbonyl group of Gly686, introducing a slight bend in the α-helix and compromising its integrity.
c.1516C>T	L506F (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-11.262	Likely Pathogenic	0.883	Likely Pathogenic	Ambiguous	0.464	Likely Benign	4.92	Destabilizing	0.8	5.76	Destabilizing	5.34	Destabilizing	0.91	Ambiguous	-3.98	Deleterious	0.999	Probably Damaging	0.997	Probably Damaging	1.62	Pathogenic	0.01	Affected	3.37	35	0	2	-1.0	34.02
c.1513T>G	Y505D (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-14.078	Likely Pathogenic	0.993	Likely Pathogenic	Likely Pathogenic	0.718	Likely Pathogenic	4.98	Destabilizing	0.1	4.72	Destabilizing	4.85	Destabilizing	2.49	Destabilizing	-9.95	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.60	Benign	0.00	Affected	3.37	35	-3	-4	-2.2	-48.09
c.2071A>C	T691P (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-13.801	Likely Pathogenic	0.905	Likely Pathogenic	Ambiguous	0.214	Likely Benign	5.04	Destabilizing	0.4	6.09	Destabilizing	5.57	Destabilizing	1.27	Destabilizing	-3.43	Deleterious	1.000	Probably Damaging	0.952	Probably Damaging	3.43	Benign	0.06	Tolerated	3.43	14	0	-1	-0.9	-3.99	188.9	33.0	0.1	0.0	-0.6	0.0	X	X						Potentially Pathogenic	The hydroxyl side chain of Thr691, located in an α-helix (res. Leu696-Leu685), can form hydrogen bonds with the backbone carbonyl and the side chain guanidinium group of Arg687. This interaction facilitates the simultaneous formation of salt bridges between Arg687 and Glu688 on the same α-helix. Additionally, Thr691 occasionally interacts with the thioether side chain of Met409 in an anti-parallel β-sheet of the C2 domain (res. Ile411-Ala399), although this interaction is not consistently maintained throughout the WT simulations. In the variant simulations, the pyrrolidine side chain of Pro691 lacks hydrogen bond donors, making a similar setup impossible. Moreover, proline lacks a free amide group necessary for hydrogen bonding with the carbonyl group of Arg687, introducing a slight bend in the α-helix and compromising its integrity.
c.1406C>A	A469D (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.643	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.738	Likely Pathogenic	5.09	Destabilizing	0.2	4.16	Destabilizing	4.63	Destabilizing	1.68	Destabilizing	-3.48	Deleterious	0.999	Probably Damaging	0.996	Probably Damaging	-1.34	Pathogenic	0.21	Tolerated	3.37	34	0	-2	-5.3	44.01	237.0	-58.2	-0.2	0.1	0.8	0.1	X		X					Potentially Pathogenic	The methyl group of Ala469, located in an α helix (res. Ala461–Phe476), interacts with hydrophobic residues (e.g., Trp572, Leu588, Met470) in an inter-helix space formed by two other α helices (res. Glu582–Ser604, res. Arg563–Gly580). In the variant simulations, Asp469 introduces a negatively charged and bulky side chain into the hydrophobic niche. Consequently, the side chain of Asp469 rotates outward, allowing the carboxylate group to form a salt bridge with the guanidinium group of Arg575 on the protein surface. This interaction affects the continuity of the parent α helix (Ala461–Phe476). Due to the importance of hydrophobic packing, the structural effects could be more pronounced during actual protein folding.
c.1160G>T	G387V (3D Viewer)	Likely Benign	C2	Uncertain		1	6-33438065-G-T	22	1.37e-5	-6.199	Likely Benign	0.153	Likely Benign	Likely Benign	0.390	Likely Benign	5.13	Destabilizing	1.8	6.44	Destabilizing	5.79	Destabilizing	-0.33	Likely Benign	-0.54	Neutral	0.069	Benign	0.077	Benign	1.32	Pathogenic	0.01	Affected	4.32	3	-1	-3	4.6	42.08	207.7	-68.4	-0.7	0.8	-0.5	0.1								Uncertain	Gly387 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364 and res. Ala399-Ile411). The Ω loop is assumed to directly interact with the membrane, and it is observed to move arbitrarily throughout the WT solvent simulations. This loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone.Ω loops are known to play significant roles in protein functions that require flexibility, and thus hydrophobic residues like valine are rarely tolerated. Although no negative structural effects are visualized in the variant’s simulations, Val387 may exert drastic effects on the SynGAP-membrane complex dynamics and stability. Since the effects on the Gly-rich Ω loop dynamics can only be well studied through the SynGAP-membrane complex, no definite conclusions can be drawn.
c.1118G>T	G373V (3D Viewer)	Likely Benign	C2	Uncertain		1	6-33438023-G-T	6	5.03e-6	-6.062	Likely Benign	0.112	Likely Benign	Likely Benign	0.428	Likely Benign	5.32	Destabilizing	3.2	0.82	Ambiguous	3.07	Destabilizing	0.09	Likely Benign	-0.98	Neutral	0.007	Benign	0.001	Benign	3.90	Benign	0.00	Affected	3.53	16	-1	-3	4.6	42.08	207.6	-68.1	1.9	1.1	-0.6	0.1								Uncertain	Gly373 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364, res. Ala399-Ile411). Because the Ω loop is assumed to directly interact with the membrane, it moves arbitrarily throughout the WT solvent simulations. The Ω loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone.Ω loops are known to play major roles in protein functions that require flexibility, and thus hydrophobic residues like valine are rarely tolerated. Although no negative structural effects are observed in the variant simulations, Val373 may exert drastic effects on the SynGAP-membrane complex dynamics and stability. However, since the effect on the Gly-rich Ω loop dynamics can only be studied through the SynGAP-membrane complex, no definite conclusions can be drawn.
c.1259T>C	F420S (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-13.231	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.544	Likely Pathogenic	5.34	Destabilizing	0.1	5.73	Destabilizing	5.54	Destabilizing	2.14	Destabilizing	-7.43	Deleterious	0.998	Probably Damaging	0.938	Probably Damaging	3.09	Benign	0.00	Affected	3.37	29	-3	-2	-3.6	-60.10	213.3	57.8	0.0	0.0	-0.4	0.1							X	Potentially Pathogenic	In the WT, the phenyl ring of the Phe420 side chain, located on an α helix (res. Met414-Glu436), packs against hydrophobic residues in the interhelix area of the GAP domain (e.g., Leu689, Leu714, Leu717, Leu718). Although no large-scale adverse effects are seen in the variant simulations, the polar hydroxyl group of Ser420 is not suitable for the hydrophobic inter-helix space. Thus, the residue swap could affect protein folding. In theory, the introduced hydroxyl group could also lower the α helix integrity by H-bonding with the backbone atoms of neighboring residues in the same α helix. However, no such effect is seen in the variant simulations.
c.980T>C	L327P (3D Viewer)	Likely Pathogenic	C2	Pathogenic		3				-16.602	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.658	Likely Pathogenic	5.38	Destabilizing	0.1	4.00	Destabilizing	4.69	Destabilizing	2.62	Destabilizing	-5.97	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	1.52	Pathogenic	0.01	Affected	3.38	23	-3	-3	-5.4	-16.04	221.7	69.4	0.1	0.0	0.6	0.1	X							Potentially Pathogenic	The backbone amide group of Leu327, located in the middle of an anti-parallel β sheet strand (res. Ala322-Asp330), forms a hydrogen bond with the carbonyl group of Gly344 on a neighboring β strand (res. Lys336-Pro349) in the WT simulations. In contrast, in the variant simulations, the introduction of Pro327 destabilizes the hydrogen bonding between the two anti-parallel β strands because proline lacks the backbone amide group altogether. Additionally, in the WT simulations, the iso-butyl side chain of Leu327 packs against multiple hydrophobic residues (e.g., Leu274, V400, Val343), whereas the less bulky cyclic five-membered pyrrolidine ring of Pro327 cannot fill the same space as effectively. Thus, although no large-scale unfolding is observed during the variant simulations, the residue swap is likely to cause severe problems for the correct C2 domain folding, which could also affect the SynGAP-membrane association.	10.1016/j.ajhg.2020.11.011
c.922T>C	W308R (3D Viewer)	Likely Pathogenic	C2	Pathogenic		1				-12.264	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.868	Likely Pathogenic	5.40	Destabilizing	0.5	4.27	Destabilizing	4.84	Destabilizing	1.88	Destabilizing	-12.87	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	0.48	Pathogenic	0.00	Affected	3.38	19	2	-3	-3.6	-30.03	290.4	-26.7	-0.1	0.1	0.0	0.2	X		X				X	Potentially Pathogenic	The indole ring of Trp308, located in an anti-parallel β sheet strand (res. Thr305-Asn315), packs against multiple hydrophobic residues (e.g., Ile268, Val306, Cys282). The indole group of Trp308 also hydrogen bonds with the backbone atoms of the C2 domain residues forming the anti-parallel β sheet (e.g., Tyr280, Thr294). The guanidinium group of Arg308 is comparably sized to the tryptophan it replaced; however, it is also positively charged.In the variant simulations, the charged side chain remains buried deep in the hydrophobic part of the C2 domain, where it forms new hydrogen bonds with the backbone carbonyl atoms of surrounding residues (e.g., Val306, Ile268). However, the residue swap is likely to disrupt the hydrophobic packing during folding. At a minimum, the residue swap could affect the C2 domain stability and membrane association.
c.1517T>C	L506P (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-12.088	Likely Pathogenic	0.998	Likely Pathogenic	Likely Pathogenic	0.737	Likely Pathogenic	5.48	Destabilizing	0.7	10.19	Destabilizing	7.84	Destabilizing	2.50	Destabilizing	-6.96	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	1.55	Pathogenic	0.00	Affected	3.37	35	-3	-3	-5.4	-16.04	182.6	64.9	0.1	0.0	0.2	0.1	X							Potentially Pathogenic	Leu506 is located in the middle of an α-helix (res. Gly502-Tyr518) within the inter-helix space of two helices (res. Gly502-Tyr518 and res. Glu582-Met603). In the WT simulations, the iso-butyl side chain of Leu506 hydrophobically packs with residues in the inter-helix space (e.g., Ile510, Phe597, Leu598, Ala601). In the variant simulations, the cyclic five-membered pyrrolidine ring of Pro506 is not as optimal as Leu506 for hydrophobic packing with nearby residues. Additionally, Pro506 cannot maintain the hydrogen bond with the backbone oxygen of Gly502 as Leu506 does in the WT, which disrupts the secondary structure element.
c.924G>C	W308C (3D Viewer)	Likely Pathogenic	C2	Pathogenic/Likely path.		2				-12.791	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.738	Likely Pathogenic	5.56	Destabilizing	0.3	4.38	Destabilizing	4.97	Destabilizing	1.26	Destabilizing	-11.95	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	0.48	Pathogenic	0.00	Affected	3.38	19	-8	-2	3.4	-83.07	230.8	60.5	-0.3	0.1	-0.4	0.4							X	Potentially Pathogenic	The indole ring of Trp308, located in an anti-parallel β sheet strand (res. Thr305-Asn315), packs against multiple hydrophobic residues (e.g., Ile268, Val306, Cys282). The indole group of Trp308 also hydrogen bonds with the backbone atoms of the C2 domain residues forming the anti-parallel β sheet (e.g., Tyr280, Thr294). The introduced Cys308 is smaller than the tryptophan it replaced. The thiol group of the Cys308 side chain is well-suited for the inner hydrophobic part of the C2 domain. Although the negative effects are essentially missing from the simulations, the side chain size difference between the residues is likely to disrupt the hydrophobic packing during folding. At a minimum, the residue swap could affect the C2 domain stability and membrane association.
c.1763T>C	L588P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.771	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.932	Likely Pathogenic	5.61	Destabilizing	0.5	12.91	Destabilizing	9.26	Destabilizing	2.33	Destabilizing	-6.97	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.42	Pathogenic	0.00	Affected	3.38	34	-3	-3	-5.4	-16.04
c.1706T>C	F569S (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		2				-13.384	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.916	Likely Pathogenic	5.70	Destabilizing	0.1	5.38	Destabilizing	5.54	Destabilizing	2.45	Destabilizing	-7.97	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.32	Pathogenic	0.00	Affected	3.37	34	-3	-2	-3.6	-60.10	213.7	67.9	-0.1	0.0	-1.0	0.1							X	Potentially Pathogenic	Phe569 is located on an α-helix (res. Arg563-Glu578). In the WT simulations, the phenyl side chain of Phe569 packs with hydrophobic residues such as Trp572, Leu565, Ile589, Ile667, and Phe561, originating from three different α-helices (res. Ala533-Val560, res. Arg563-Glu578, and res. Ser641-Glu666). In the variant simulations, the acceptor/donor hydroxyl group of Ser569 forms hydrogen bonds with the carbonyl groups of Glu567 and Lys566 on the same α-helix, which could affect the α-helix integrity, although this is not observed in the simulations. While the simulations do not show large-scale effects, the residue swap could have a substantial impact on the protein structure due to the fundamental role of hydrophobic packing during protein folding.
c.791T>C	L264P (3D Viewer)	Likely Pathogenic	C2	Uncertain		1				-12.285	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.767	Likely Pathogenic	5.73	Destabilizing	0.3	6.57	Destabilizing	6.15	Destabilizing	2.65	Destabilizing	-6.43	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	0.49	Pathogenic	0.00	Affected			-3	-3	-5.4	-16.04
c.1778T>C	L593P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-13.961	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.777	Likely Pathogenic	5.75	Destabilizing	0.9	10.77	Destabilizing	8.26	Destabilizing	2.43	Destabilizing	-6.77	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.77	Benign	0.00	Affected			-3	-3	-5.4	-16.04
c.1715G>C	W572S (3D Viewer)	Likely Pathogenic	GAP	Pathogenic		1				-17.461	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.775	Likely Pathogenic	5.78	Destabilizing	0.2	3.37	Destabilizing	4.58	Destabilizing	1.79	Destabilizing	-12.74	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.24	Pathogenic	0.01	Affected	3.37	35	-2	-3	0.1	-99.14	235.1	76.6	0.0	0.0	-0.4	0.1							X	Potentially Pathogenic	The introduced residue Ser572, located in an α-helix (res. Arg563-Glu578), is considerably smaller than the tryptophan it replaced. The indole ring of the Trp572 side chain lies in a hydrophobic inter-helix space, where it makes extensive hydrophobic interactions with nearby residues such as Met470, Phe569, Leu588, and Ile589. In the variant simulations, all these favorable packing interactions are completely removed, as the introduced residue Ser572 is too hydrophilic or small to fill the hydrophobic niche occupied by the indole ring. Moreover, the hydroxyl group of Ser572 forms hydrogen bonds with the carbonyl groups of Glu567 and Val568 within the same α-helix, potentially lowering its integrity. Overall, the residue swap is highly likely to cause critical protein folding problems that are underestimated based on the effects seen in the variant simulations.
c.1147G>T	G383W (3D Viewer)		C2	Uncertain		1	6-33438052-G-T	1	6.22e-7	-10.161	Likely Pathogenic	0.439	Ambiguous	Likely Benign	0.469	Likely Benign	5.81	Destabilizing	3.6	4.44	Destabilizing	5.13	Destabilizing	0.08	Likely Benign	-1.01	Neutral	0.959	Probably Damaging	0.704	Possibly Damaging	4.09	Benign	0.00	Affected	4.32	7	-2	-7	-0.5	129.16
c.851T>C	L284P	Likely Pathogenic	C2	Likely Pathogenic		1				-15.588	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.794	Likely Pathogenic	5.83	Destabilizing	0.2	5.81	Destabilizing	5.82	Destabilizing	1.89	Destabilizing	-6.17	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	1.64	Pathogenic	0.00	Affected			-3	-3	-5.4	-16.04
c.1499T>C	L500P (3D Viewer)	Likely Pathogenic	GAP	Pathogenic		1				-15.898	Likely Pathogenic	0.996	Likely Pathogenic	Likely Pathogenic	0.894	Likely Pathogenic	5.91	Destabilizing	0.3	8.90	Destabilizing	7.41	Destabilizing	1.92	Destabilizing	-6.96	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.37	Pathogenic	0.01	Affected	3.37	35	-3	-3	-5.4	-16.04
c.1714T>G	W572G (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-17.692	Likely Pathogenic	0.997	Likely Pathogenic	Likely Pathogenic	0.900	Likely Pathogenic	6.57	Destabilizing	0.2	7.57	Destabilizing	7.07	Destabilizing	1.83	Destabilizing	-11.98	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.24	Pathogenic	0.00	Affected	3.37	35	-7	-2	0.5	-129.16	195.2	127.9	0.0	0.0	-1.0	0.0							X	Potentially Pathogenic	The introduced residue Gly572, located in an α-helix (res. Arg563-Glu578), is considerably smaller than the tryptophan it replaced. The indole ring of the Trp572 side chain lies in a hydrophobic inter-helix space, where it makes extensive hydrophobic interactions with nearby residues such as Met470, Phe569, Leu588, and Ile589. In the variant simulations, all these favorable packing interactions are completely removed, as the introduced residue Gly572 essentially lacks a side chain altogether. Although not observed in the simulations, the residue swap could also weaken the integrity of the helix (res. Arg563-Glu578), as glycine is known as an “α-helix breaker.” Overall, the residue swap is highly likely to cause critical protein folding problems that are underestimated based on the effects seen in the variant simulations.
c.1898T>C	L633P (3D Viewer)	Likely Pathogenic	GAP	Pathogenic/Likely path.		2				-15.669	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.693	Likely Pathogenic	6.60	Destabilizing	0.2	10.15	Destabilizing	8.38	Destabilizing	2.42	Destabilizing	-6.97	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.70	Benign	0.00	Affected	3.37	34	-3	-3	-5.4	-16.04	193.2	65.1	0.0	0.0	0.1	0.0	X							Potentially Pathogenic	The iso-butyl side chain of Leu633, located in the middle of an α helix (res. Glu617-Asn635), packs hydrophobically with nearby residues (e.g., Leu653, Val629, Leu551) in the WT simulations.In the variant simulations, the pyrrolidine side chain of Pro633 is not as optimal for hydrophobic packing as Leu633 in the WT. Additionally, proline lacks a free backbone amide group, so Pro633 cannot form a hydrogen bond with the backbone carbonyl group of Val629, which disrupts the continuity of the secondary structure element.
c.1652T>C	L551P (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-14.620	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.953	Likely Pathogenic	6.66	Destabilizing	0.1	6.58	Destabilizing	6.62	Destabilizing	2.66	Destabilizing	-4.70	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-1.60	Pathogenic	0.01	Affected	3.37	35	-3	-3	-5.4	-16.04	208.6	60.9	0.1	0.0	-0.3	0.0	X							Potentially Pathogenic	L551 is located on an α-helix (res. Ala533-Val560). The iso-butyl side chain of Leu551 hydrophobically packs with nearby hydrophobic residues such as Cys547, Phe652, Leu633, and Ile630 in the inter-helix space. In the variant simulations, the pyrrolidine side chain of Pro551 is not as optimal as leucine for hydrophobic packing with the nearby residues. Moreover, Pro551 lacks the amide group, and thus, it cannot form a hydrogen bond with the backbone carbonyl group of Cys547, which disrupts the continuity of the secondary structure element.
c.2087T>C	L696P (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-16.926	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.678	Likely Pathogenic	6.66	Destabilizing	0.2	10.84	Destabilizing	8.75	Destabilizing	2.13	Destabilizing	-6.58	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	3.00	Benign	0.00	Affected	3.46	13	-3	-3	-5.4	-16.04	180.6	65.9	0.1	0.0	-0.6	0.1	X							Potentially Pathogenic	The isobutyl side chain of Leu696, located in the middle of an α-helix (res. Leu685-Gln702), engages in hydrophobic packing with nearby residues (e.g., Leu441, Leu431, Leu692, Leu714) in the inter-helix space. Prolines lack a free amide group necessary for hydrogen bonding with the carbonyl group of Leu692 in the same manner as Leu696 in the WT. Consequently, the residue swap with proline disrupts the continuity of the secondary structure element in the variant simulations. Additionally, the side chain of Pro696 is not as optimal as Leu696 for hydrophobic packing in the inter-helix space.
c.1802C>A	A601E (3D Viewer)	Likely Pathogenic	GAP	Conflicting		2				-16.752	Likely Pathogenic	0.992	Likely Pathogenic	Likely Pathogenic	0.588	Likely Pathogenic	6.68	Destabilizing	0.8	5.76	Destabilizing	6.22	Destabilizing	1.24	Destabilizing	-4.98	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	2.54	Benign	0.00	Affected	3.37	35	0	-1	-5.3	58.04	240.0	-82.3	0.0	0.0	0.7	0.1		X	X				X	Potentially Pathogenic	The methyl side chain of Ala601, located on an α helix (res. Glu582-Met603), packs hydrophobically against other hydrophobic residues in the inter-helix space (e.g., Phe597, Leu598, Leu506, Phe608).In the variant simulations, the carboxylate group of Glu601 faces the inter-helix space and is forced to shift slightly away from the hydrophobic niche. Additionally, in two of the simulations, Glu601 forms a salt bridge with Arg499, causing the otherwise stable salt bridge between Arg499 and Glu496 at the outer surface of an α helix (res. Leu489-Glu519) to break due to the residue swap.These effects suggest that the protein folding process could be seriously affected. Moreover, due to its location at the GAP-Ras interface, it could also impact the complex formation with the GTPase.
c.1481T>G	I494R (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-15.758	Likely Pathogenic	0.995	Likely Pathogenic	Likely Pathogenic	0.911	Likely Pathogenic	6.71	Destabilizing	0.3	3.40	Destabilizing	5.06	Destabilizing	2.19	Destabilizing	-6.43	Deleterious	0.999	Probably Damaging	0.957	Probably Damaging	-1.41	Pathogenic	0.00	Affected	3.37	35	-2	-3	-9.0	43.03	273.9	-59.8	0.0	0.0	0.0	0.1	X	X	X				X	Potentially Pathogenic	The sec-butyl side chain of Ile494, located in an α-helix (res. Leu489-Glu519), packs against hydrophobic residues (e.g., Phe484, Leu465, Trp572, Ala493, Met468) in an inter-helix space (res. Leu489-Glu519 and res. Ala461-Phe476). In the variant simulations, the bulkier and positively charged residue, Arg494, weakens the integrity of the opposing helix. Additionally, the bulkier Arg494 stacks with Phe484, causing the α-helices to move farther apart to accommodate it. This mutation could have substantial negative effects due to the fundamental role of hydrophobic packing, which is disrupted by Arg494 during protein folding.
c.1292T>C	L431P (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-14.222	Likely Pathogenic	0.996	Likely Pathogenic	Likely Pathogenic	0.659	Likely Pathogenic	6.78	Destabilizing	0.3	11.59	Destabilizing	9.19	Destabilizing	2.29	Destabilizing	-6.39	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	2.91	Benign	0.05	Affected	3.37	29	-3	-3	-5.4	-16.04	222.4	62.8	0.1	0.0	0.1	0.0	X							Potentially Pathogenic	The iso-butyl side chain of Leu431, located in an α helix (res. Met414-Glu436), packs against other hydrophobic residues in an interhelix space (e.g., Val434, Leu435, Leu696, Leu711) in the WT simulations. While the backbone amide group of Leu431 forms an H-bond with the carbonyl group of His427, the cyclic five-membered pyrrolidine ring of Pro431, lacking the necessary amide group, cannot do the same. Thus, although the cyclic five-membered pyrrolidine ring of Pro431 packs almost as favorably as the side chain of Leu431 in the hydrophobic niche, the residue swap causes the α helix to partially unfold in the variant simulations.
c.1352T>C	L451P (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-14.549	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.750	Likely Pathogenic	6.92	Destabilizing	0.2	8.57	Destabilizing	7.75	Destabilizing	2.58	Destabilizing	-6.81	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.43	Pathogenic	0.00	Affected	3.37	34	-3	-3	-5.4	-16.04
c.1142G>T	G381V (3D Viewer)	Likely Benign	C2	Uncertain		1	6-33438047-G-T	2	1.25e-6	-5.967	Likely Benign	0.146	Likely Benign	Likely Benign	0.618	Likely Pathogenic	7.16	Destabilizing	1.0	4.10	Destabilizing	5.63	Destabilizing	-0.32	Likely Benign	-0.95	Neutral	0.386	Benign	0.157	Benign	1.32	Pathogenic	0.10	Tolerated	4.32	9	-1	-3	4.6	42.08	214.6	-68.8	0.3	0.7	-0.5	0.3								Uncertain	Gly381 is located in the Gly-rich Ω loop (res. Pro364-Pro398) between two anti-parallel β sheet strands (res. Thr359-Pro364, res. Ala399-Ile411). Because the Ω loop is assumed to directly interact with the membrane, it moves arbitrarily throughout the WT solvent simulations. The Ω loop potentially plays a crucial role in the SynGAP-membrane complex association, stability, and dynamics. However, this aspect cannot be fully addressed through solvent simulations alone.Ω loops are known to play major roles in protein functions that require flexibility, and thus hydrophobic residues like valine are rarely tolerated. Although no negative structural effects are observed in the variant simulations, Val381 may exert drastic effects on the SynGAP-membrane complex dynamics and stability. However, since the effects on Gly-rich Ω loop dynamics can only be well studied through the SynGAP-membrane complex, no definite conclusions can be drawn.
c.1394T>C	L465P (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-14.824	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.778	Likely Pathogenic	7.18	Destabilizing	0.3	10.85	Destabilizing	9.02	Destabilizing	2.73	Destabilizing	-6.96	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	2.29	Pathogenic	0.00	Affected	3.37	34	-3	-3	-5.4	-16.04	211.1	65.9	0.1	0.0	-0.2	0.0	X							Potentially Pathogenic	The iso-butyl side chain of Leu465, located in the middle of an α helix (res. Ala461–Phe476), packs with hydrophobic residues (e.g., Phe464, Met468, Tyr497, Ile494) in an inter-helix space formed with two other α helices (res. Ala461–Phe476 and res. Thr488-Gly502). In the variant simulations, the cyclic five-membered pyrrolidine ring of Pro465 is not as optimal as the side chain of Leu465 for filling the three α helix hydrophobic niche. Although the residue swap does not cause a large-scale conformational shift during the simulations, the H-bond between the backbone amide group of Leu465 and the backbone carbonyl group of Ala461 is lost. This, in turn, breaks the continuity of the α helix secondary structure element.
c.1726T>C	C576R (3D Viewer)	Likely Pathogenic	GAP	Conflicting		2				-14.886	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.579	Likely Pathogenic	7.20	Destabilizing	1.0	4.09	Destabilizing	5.65	Destabilizing	1.64	Destabilizing	-10.88	Deleterious	0.999	Probably Damaging	0.996	Probably Damaging	3.38	Benign	0.00	Affected	3.37	35	-3	-4	-7.0	53.05
c.1639T>C	C547R (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-16.967	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.900	Likely Pathogenic	7.76	Destabilizing	0.8	5.83	Destabilizing	6.80	Destabilizing	1.69	Destabilizing	-11.60	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	-1.33	Pathogenic	0.02	Affected	3.37	35	-4	-3	-7.0	53.05	267.4	-90.3	0.0	0.0	-0.1	0.1	X	X	X				X	Potentially Pathogenic	Cys547 is located in an α-helix (res. Ala533-Val560). The thiol side chain of Cys is situated in a hydrophobic inter-helix space, where it packs hydrophobically with other residues such as Ile626, Leu551, and Phe652. Additionally, the thiol side chain of Cys547 weakly hydrogen bonds with the carbonyl group of Leu543 in the same α-helix. In the variant simulations, the bulkier, positively charged guanidinium group of Arg547 must rotate out of the hydrophobic space. Consequently, it forms ionic interactions with the carboxylate groups of Glu548 in the same helix and Glu656 in the neighboring α-helix (res. Glu666-Asp644). This causes the two helices to slightly separate, significantly affecting the secondary structure integrity of the latter helix. These negative structural effects could be more pronounced during protein folding and are likely to be undermined in the MD simulations.
c.1640G>A	C547Y (3D Viewer)	Likely Pathogenic	GAP	Pathogenic		1				-15.871	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.874	Likely Pathogenic	8.53	Destabilizing	1.8	6.20	Destabilizing	7.37	Destabilizing	0.62	Ambiguous	-10.57	Deleterious	1.000	Probably Damaging	0.998	Probably Damaging	-1.33	Pathogenic	0.06	Tolerated	3.37	35	0	-2	-3.8	60.04	280.1	-54.8	0.0	0.0	0.0	0.0		X	X				X	Potentially Pathogenic	Cys547 is located in an α-helix (res. Ala533-Val560). The thiol side chain of Cys547 is situated in a hydrophobic inter-helix space, where it packs hydrophobically with other residues such as Ile626, Leu551, and Phe652. Additionally, the thiol side chain of Cys weakly hydrogen bonds with the carbonyl group of Leu543 in the same α-helix. In the variant simulations, the bulkier phenol ring of Tyr547, with its polar hydroxyl group, is less suited for the hydrophobic space. Consequently, it moves outside and forms a hydrogen bond with the carbonyl group of Phe652 in the neighboring α-helix (res. Glu666-Asp644). This causes the two helices to slightly separate, negatively affecting the secondary structure integrity of the latter helix. These negative structural effects could be more pronounced during protein folding and are likely to be undermined in the MD simulations.
c.1814C>G	P605R (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-13.745	Likely Pathogenic	0.996	Likely Pathogenic	Likely Pathogenic	0.845	Likely Pathogenic	8.71	Destabilizing	2.5	6.46	Destabilizing	7.59	Destabilizing	0.92	Ambiguous	-8.95	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	0.69	Pathogenic	0.00	Affected	3.37	35	0	-2	-2.9	59.07	281.7	-118.1	-0.2	0.0	0.5	0.1		X	X	X			X	Potentially Pathogenic	Pro605 is located in a short turn between an α helix (res. Glu582-Met603) and a short α helical section (res. Ser606-Phe608). The pyrrolidine side chain of Pro605 packs hydrophobically with nearby hydrophobic residues (e.g., Ile514, Leu623, Leu610) in the inter-helix space. Additionally, proline lacks a free backbone amide group, which breaks the α helix and facilitates the turn in the WT structure.In the variant simulations, the guanidinium side chain of Arg605 is bulkier than proline, and its positively charged guanidinium group faces mostly hydrophobic residues (e.g., Ile514, Leu623, Leu610). As a result, it needs to rotate away from the hydrophobic niche. The residue swap could have a more profound effect on the actual folding process, for example, by preventing the bending at the α helix end.Moreover, due to its location at the GAP-Ras interface, the residue swap could affect the GAP-Ras association.
c.1030G>A	G344S (3D Viewer)	Likely Pathogenic	C2	Pathogenic		5				-11.254	Likely Pathogenic	0.986	Likely Pathogenic	Likely Pathogenic	0.790	Likely Pathogenic	9.02	Destabilizing	0.7	6.08	Destabilizing	7.55	Destabilizing	0.98	Ambiguous	-5.28	Deleterious	1.000	Probably Damaging	1.000	Probably Damaging	-0.45	Pathogenic	0.04	Affected	3.37	25	1	0	-0.4	30.03	217.3	-51.7	0.0	0.1	0.2	0.1			X				X	Potentially Pathogenic	Because Gly344 lacks a proper side chain, it allows the anti-parallel β sheet strand (res. Gly341-Pro349) to have a slight twist. Within a β strand, side chains normally alternate between outward and inward positions, but glycine is an exception as it allows the alternating pattern to skip a residue. Introducing serine or any other residue with a side chain at position 344 prevents this unique skip in the alternating pattern, causing structural strain or likely preventing correct folding altogether. Additionally, Tyr342 shields Gly344 from the solvent, contributing to twist formation in the β sheet and stabilizing the β-strand.In the variant simulations, the side chain of Ser344 assumes the inward position. However, the hydrophobic niche formed by multiple C2 domain residues (e.g., Val365, Val343, Leu327) is not accommodating for its hydroxyl group. The outward position, not seen in the simulations, would be equally disadvantageous due to the presence of hydrophobic residues on that side as well (e.g., Leu345, Tyr342). Serine is also not well-suited for twist formation, as it tends to suppress twisting and bending in β sheets. At this position, the hydroxyl group of Ser344 could also form hydrogen bonds with the backbone atoms of the Gly-rich Ω loop in the C2 domain (e.g., Thr366, Leu367, Gly378; res. Pro364-Pro398), potentially adversely affecting membrane-loop dynamics and ultimately compromising the stability of the SynGAP-membrane association.
c.2075T>C	L692P (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-16.447	Likely Pathogenic	1.000	Likely Pathogenic	Likely Pathogenic	0.668	Likely Pathogenic	9.19	Destabilizing	0.1	13.20	Destabilizing	11.20	Destabilizing	1.69	Destabilizing	-6.98	Deleterious	1.000	Probably Damaging	0.999	Probably Damaging	3.06	Benign	0.00	Affected	3.42	17	-3	-3	-5.4	-16.04	186.2	62.8	-0.2	0.1	-0.7	0.3	X							Potentially Pathogenic	The isobutyl side chain of Leu692, located in the middle of an α-helix (res. Leu685-Gln702), engages in hydrophobic packing with nearby residues (e.g., Leu441, Leu431, Leu696) in the inter-helix space. Prolines lack a free amide group necessary for hydrogen bonding with the carbonyl group of Glu688 in the same manner as Leu692 in the WT. Consequently, the residue swap with proline disrupts the continuity of the secondary structure element in the variant simulations. Additionally, the side chain of Pro692 is not as optimal as Leu692 for hydrophobic packing in the inter-helix space.
c.1354G>T	V452F (3D Viewer)	Likely Pathogenic	GAP	Uncertain		1				-14.769	Likely Pathogenic	0.975	Likely Pathogenic	Likely Pathogenic	0.511	Likely Pathogenic	9.21	Destabilizing	0.1	0.37	Likely Benign	4.79	Destabilizing	0.61	Ambiguous	-4.94	Deleterious	0.999	Probably Damaging	0.993	Probably Damaging	3.29	Benign	0.00	Affected	3.37	34	-1	-1	-1.4	48.04	249.4	-35.7	0.0	0.0	0.4	0.1							X	Potentially Pathogenic	The iso-propyl side chain of Val452, located in the middle of an α helix (res. Val441-Ser457), packs against hydrophobic residues in the inter-helix space at the intersection of three α helices (e.g., Leu500, His453, Leu465). In the variant simulations, the larger side chain of Phe452 cannot pack against the opposing α helix (res. Leu489-Glu519) as efficiently as valine. Due to space restrictions, the phenol ring adjusts to make room by rotating slightly sideways in the inter-helix space. Besides this small and local shift, no large-scale effects on the protein structure are seen based on the simulations. However, the size difference between the swapped residues could affect the protein folding process.
c.2003C>T	S668F (3D Viewer)	Likely Pathogenic	GAP	Likely Pathogenic		1				-15.047	Likely Pathogenic	0.999	Likely Pathogenic	Likely Pathogenic	0.643	Likely Pathogenic	16.72	Destabilizing	5.0	11.07	Destabilizing	13.90	Destabilizing	0.00	Likely Benign	-5.98	Deleterious	0.999	Probably Damaging	0.935	Probably Damaging	3.18	Benign	0.00	Affected	3.38	28	-3	-2	3.6	60.10	250.9	-59.6	-0.1	0.1	0.0	0.1		X	X				X	Potentially Pathogenic	In the WT simulations, the hydroxyl side chain of Ser668, located on an α-α loop connecting the two α-helices (res. Ser641-Glu666 and res. Leu685-Val699), forms hydrogen bonds with the backbone carbonyl groups of Leu664, Tyr665, and Glu666, as well as the guanidinium group of Arg573 on a nearby α-helix (res. Arg563-Glu578). In the variant simulations, the side chain of Phe668 cannot maintain the same hydrogen-bond network. Due to its larger size, it moves away to avoid steric hindrance. In the WT simulations, a network of hydrogen bonds between several residues (e.g., Asn669, Lys566, and Glu666) keeps both α-helices and the proceeding loop (res. Asn669-Asp684) tightly connected, but this setup is not present in the variant simulations. Additionally, in the variant simulations, the side chain of Arg573 shifts to form a more stable salt bridge with the carboxylate group of Glu582 instead of hydrogen bonding with Ser668 as in the WT simulations.